Tin(IV) and organotin(IV) complexes containing mono or bidentate N-donor ligands : III.1 1-methylimidazole derivatives: Synthesis, spectroscopic and structural characterization

Article abstract of DOI:10.1016/S0022-328X(97)00606-2

A series of adducts of the type [(L^#)_yR_nSnX_4-n]·zH ₂O (L^#=1-methylimidazole, y=1 or 2, R=Me, Et, Buⁿ or Ph, n=1, 2 or 3, X=Cl, Br or I, z=0, 1/2 or 1) has been characterized in the solid state and in solution by analyses, spectral (IR, ¹¹⁹Sn Moessbauer, and ¹H, ¹³C and ¹¹⁹Sn NMR) data and conductivity measurements. The molecular weight determinations and the NMR data indicate that these organotin(IV) complexes partly dissociate in chloroform and acetone solution. The donor L^# interacts with [(CH₃)₃SnNO₃], yielding the 2:1 ionic complex [(L^#)₂(CH₃)₃Sn]NO₃. The derivative [(L^#)₂(CH₃)₂SnCl₂] reacts with NaClO₄, AgNO₃, NaBPh₄ and KSCN in ethanol and diethyl ether giving the complexes [(L^#)₂(CH₃)₂Sn(ClO₄) ₂], [(L^#)(CH₃)₂Sn(NO₃) ₂(H₂O)], [(L^#)(CH₃)₂SnCl(H₂O) ₂]BPh₄ and [(L^#)₂(CH₃)₂Sn(NCS)₂], respectively, whereas when [(L^#)(CH₃)₃SnCl] interacts with an equimolar quantity of NaClO₄, [(L^#)₂(CH₃)₃Sn]ClO ₄·1/2H₂O and (CH₃)₃Sn(ClO₄) in 1:1 ratio are obtained. The stability towards self-decomposition of the complexes obtained decreases with increasing number of the Sn-bonded aryl or alkyl groups. The derivative [(L^#)₂(CH₃)₂SnBr₂] reacts with 1,10-phenanthroline (Phen), yielding immediately the complex [(Phen)(CH₃)₂SnBr₂], whereas from the reaction between [(L^#)₂(CH₃)₂Sn(ClO₄) ₂] and Phen, the mixed ligand complex [(L^#)(Phen)(CH₃)₂Sn](ClO₄) ₂ is obtained. A different behaviour has been shown from the diiodide complex [(L^#)₂(C₂H₅)₂SnI ₂] which reacts with Phen, yielding the compound with the 3:2 stoichiometry [(Phen)₃{(C₂H₅)₂SnI ₂}₂]. Both the crystal structures of [(L^#)₂(CH₃)₂SnBr₂] and [(L^#)₂(C₂H₅)₂SnI ₂] show the tin atom in an all-trans octahedral regular configuration, whereas in [(L^#)(C₆H₅)₃SnCl] the tin atom exhibits a distorted trigonal bipyramidal geometry, with the phenyl groups in the equatorial positions. A comparison was made with structural data of other R₃SnXN-type derivatives. The molecular parameters of 1-methylimidazole in the tin(IV) complexes were used, together with other structural data in literature, to derive empirical rules concerning the imidazole donor.

Full text of DOI:10.1016/S0022-328X(97)00606-2

Ž
.
Journal of Organometallic Chemistry 553 1998 345–369
ž /
ž /
Tin IV and organotin IV complexes containing mono or bidentate
N-donor ligands
1
III. 1-methylimidazole derivatives: synthesis, spectroscopic and
structural characterization
a
a
a
b
b
b
C. Pettinari a,), M. Pellei , M. Miliani , A. Cingolani , A. Cassetta , L. Barba , A. Pifferi ,
c
E. Rivarola
`
a
Dipartimento di Scienze Chimiche, UniÕersita degli Studi, Õia S. Agostino 1, Camerino 62032, Macerata, Italy
Istituto di Strutturistica Chimica ‘G. Giacomello’, Consiglio Nazionale delle Ricerche, Padriciano 99, Trieste 30412, Italy
b
c
Dipartimento di Chimica Inorganica, UniÕersita degli Studi di Palermo, Õia Archirafi 26, Palermo 90123, Italy
`
Received 16 July 1997
Abstract
a
a
n
wŽ
.
x
Ž
A series of adducts of the type
L
yRnSnX4yn PzH2O L s1-methylimidazole, ys1 or 2, RsMe, Et, Bu or Ph, ns1, 2 or 3,
XsCl, Br or I, zs0, 1r2 or 1 has been characterized in the solid state and in solution by analyses, spectral IR, 119Sn Mossbauer, and
.
Ž
¨
1H, 13C and 119Sn NMR data and conductivity measurements. The molecular weight determinations and the NMR data indicate that these
.
a
Ž
.
wŽ
.
x
organotin IV complexes partly dissociate in chloroform and acetone solution. The donor L interacts with CH3 3SnNO3 , yielding the
CH3 3Sn NO3. The derivative
ethanol and diethyl ether giving the complexes
a
a
wŽ . Ž
.
x
wŽ . Ž
.
x
2:1 ionic complex
L
L
CH3 2SnCl2 reacts with NaClO4, AgNO3, NaBPh4 and KSCN in
2
2
Ž
a
a
a
wŽ . Ž
.
. x wŽ .Ž
.
Ž
. Ž
.x wŽ .Ž
.
Ž
. x
2
L
CH3 2Sn ClO4
,
L
CH3 2Sn NO3 H2O , L
x
CH3 2SnCl H2O BPh4
CH3 3SnCl interacts with an equimolar quantity of NaClO4,
2
2
2
a
a
wŽ . Ž
2
.
Ž
. x
wŽ .Ž
L
.
and
wŽ . Ž
L
CH3 2Sn NCS , respectively, whereas when
2
2
a
. x Ž . Ž .
CH3 3Sn ClO4 P1r2H2O and CH3 3Sn ClO4 in 1:1 ratio are obtained. The stability towards self-decomposition of the
a
L
wŽ . Ž . x
CH3 2SnBr2 reacts
2
complexes obtained decreases with increasing number of the Sn-bonded aryl or alkyl groups. The derivative
L
Ž
.
wŽ
.Ž
.Ž
.
x
with 1,10-phenanthroline Phen , yielding immediately the complex Phen CH3 2SnBr2 , whereas from the reaction between
a
a
wŽ . Ž
. Ž . x wŽ .Ž
CH3 2Sn ClO4 and Phen, the mixed ligand complex L Phen CH3 2Sn ClO4 is obtained. A different behaviour has been
2
.
xŽ
.
L
2
2
a
wŽ . Ž
.
x
shown from the diiodide complex
L
C2H5 2SnI2 which reacts with Phen, yielding the compound with the 3:2 stoichiometry
2
a
a
wŽ
. ÄŽ
.
4 x
wŽ . Ž
.
x
wŽ . Ž . x
C2H5 2SnI2 show the tin atom in an all-trans
2
Phen C2H5 2SnI2 2 . Both the crystal structures of
L
CH3 2SnBr2 and
L
3
a
wŽ .Ž
.
2 x
octahedral regular configuration, whereas in
phenyl groups in the equatorial positions. A comparison was made with structural data of other R3SnXN-type derivatives. The molecular
L
C6H5 3SnCl the tin atom exhibits a distorted trigonal bipyramidal geometry, with the
Ž
.
parameters of 1-methylimidazole in the tin IV complexes were used, together with other structural data in literature, to derive empirical
rules concerning the imidazole donor. q 1998 Elsevier Science S.A.
Ž
.
Ž
.
Keywords: Tin IV complex; Organotin IV complex; N-donor ligand; 1-methylimidazole derivative
w
x
1. Introduction
appeared in 1980 2,3 , the preliminary examination was
extended to a systematic study of the antitumor proper-
ties of tin compounds.
Organotin compounds RnSnX4yn exhibit a variety of
biological effects depending on the number n and on
the type of organic R and X groups bound to tin. Since
the first report on the antitumor activity of diorganotins
Ž
.
Recently our group has focused on studying tin IV
Ž
.
4 x
and organotin IV
complexes of imidazoles
w
Ž
.
Ä
ImH RnSnX4yn y . In determining the stoichiometry
x
of the adducts obtained from this class of donors, three
primary factors are involved: the nature of the organic
group R, of the counter-ion X, and of the donor ligand
)
Corresponding author.
1
Ž
.
w x
ImH ; besides, it is interesting to note that the acceptor
Part II is Ref. 1 .
0022-328Xr98r$19.00 q 1998 Elsevier Science S.A. All rights reserved.

(
)
346
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
ples for microanalysis were dried in vacuo to constant
Ž
.
Ž
.
weight 208C, ca. 0.1 Torr . Elemental analyses C,H,N
were performed in house with a Carlo-Erba model 1106
instrument.
IR spectra were recorded from 4000 to 100 cmy1
with a Perkin-Elmer System 2000 FT-IR instrument.
1H, 13C and 119Sn NMR spectra were recorded on a
Fig. 1. Structure of the 1-methylimidazole donor.
VXR-300 Varian spectrometer operating at room tem-
1
perature 300 MHz for H, 75 MHz for 13C and 111.9
Ž
119
.
Sn . The chemical shifts are reported in
MHz for
ppm from SiMe4 1H and 13C, calibration by internal
Ž119
strength of the tin derivatives RnSnX4yn decreases in
Ž
w x
the following order 4 :
.
.
Sn .
deuterium solvent lock and SnMe4
Melting points were taken on an IA 8100 Elec-
trothermal instrument. The electrical conductance of the
solutions was measured with a Crison CDTM 522 con-
ductimeter at room temperature. The osmometric mea-
surements were carried out at 408C, over a range of
concentrations, with a Knauer KNA0280 vapor pressure
osmometer calibrated with benzil. The solvent was Baker
Analyzed Spectrophotometric grade chloroform. The
results were reproducible to "2%.
SnX4 )RSnX3 )R2 SnX2 )R3SnX
XsNCS;F)Cl)Br)I
RsPh)Me)Et)Pr)Bu)Oct
To investigate the influence of substituents on the
imidazole ring and the role of the N–H group, which
can take part in hydrogen bonding, we previously syn-
Ž
.
thesized and characterized spectral and crystal data
Ž
.
Ž
.
several new adducts between tin IV and organotin IV
w x
119Sn Mossbauer spectra were recorded at liquid
acceptors and 1-benzylimidazole 5 and 4-phenylim-
w x
¨
idazole 1 .
As an extension of our research, we report here the
nitrogen temperature by an Elscint-Laben spectrometer
Ž
equipped with an Oxford cryostat model DN 700 Ox-
ford, UK . A Ca119SnO3 Mossbauer source, 10 mCi
Ž
.
synthesis, spectroscopic characterization IR,
¨
1
119
.
Ž
.
Mossbauer, H and Sn NMR and behaviour in solu-
from Radiochemical Centre, Amersham, UK moved
¨
Ž
.
tion conductivity and molecular weight measurements
with constant acceleration, and a triangular waveform
were used. The velocity calibration was made using a
n
Ž
of new adducts between RnSnX4yn RsMe, Et, Bu
57Co Mossbauer source, 10 mCi, and an iron foil,
and Ph; ns1, 2 or 3; XsCl, Br, I, ClO4, NO3, BPh4
¨
enriched to 95% in 57 Fe DuPont Pharma Italia, Firenze,
.
Ž
.
Ž
and NCS acceptors and 1-methylimidazole Fig. 1
a
Ž
.
.
L . This is the most extensive study of imidazole
Italy was used as absorber.
Ž
.
organotin IV compounds to date.
We report the X-ray crystal structure determinations
2.2. Syntheses
a
Ž
w
Ž
.Ž
.
x
of three of these complexes
L
C6 H 3SnCl ,
a
a
w
Ž
. Ž
.
x
w
Ž
. Ž
.
x5
.
L
CH3 2 SnBr2 and
L
C2 H5 2 SnI2 and in-
All experiments were carried out under a dinitrogen
atmosphere. Hydrocarbon solvents were dried by distil-
lation from sodium–potassium, dichloromethane from
calcium hydride and tetrahydrofuran from LiAlH4. All
solvents were outgassed with dry dinitrogen prior to
use.
2
2
vestigate the influence of halide and organic substituent
on the metal coordination geometry. We also made a
comparison with the X-ray crystal structures of several
R3SnX N-donor -type compounds and also of several
metal and organometal derivatives of 1-methylimida-
Ž
.
zole.
a
w
Ž
.
x
[
(
)
(
)] ( )
We also investigated the reactivity of L 2 R2 SnX2
system toward monodentate or bidentate N- and P-
donors.
2.2.1. Chlorotrimethyl 1-methylimidazole tin IV
1
Ž
.
a
To a stirred refrigerated 08C diethyl ether solution
100 cm of 1-methylimidazole L 1.00 g, 12.2 mmol ,
CH3 3SnCl 607 mg, 3.0 mmol was added under N2
3
Ž
Ž
.
Ž
.
.
Ž
.
stream. The mixture was stored at 08C and stirred for 12
h. The solution was stored in freezer overnight. An oil
was formed, which was separated from the solution.
2. Experimental
Ž
2.1. General methods
The residue was washed with diethyl ether 3=20
3
.
Ž
cm , dried in vacuo to constant weight 208C, ca. 0.1
Ž
.
.
The organotin IV halides were purchased from Alfa
Torr and shown to be compound 1. Yield: 80%, m.p.
66–688C Found: C, 29.6; H, 5.5; N, 10.1. Calc. for
C7 H15ClN2 Sn: C, 29.9; H, 5.4; N, 10.0% . NMR
CDCl3 : H, d 7.59, 7.07, 6.93 s, H , H and H ,
Ž
.
Ž
.
Ž
Karlsruhe and Aldrich Milwaukee and used as re-
a
Ž
.
.
ceived. The ligand 1-methylimidazole L was ob-
tained from Aldrich and was crystallized from diethyl
1
2
4
5
Ž
.
Ž
.
w<2 Ž119
.<
Ž
.
Ž
.
etherrpetroleum ether 1:2 . Solvent evaporations were
3.74 s, 1-Me , 0.71
J
Sn–H s 64.9 Hz,
2
J
Sn–H s62.0 Hz, s, SnMe ; 13C, d 34.5 s,
. x Ž
Ž117
<
Ž
.
<
always carried out in vacuo water aspirator . The sam-

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
347
2
4
5
.
Ž
.
Ž
13
Ž
.
1-Me , 121.1, 128.0, 137.6 s, C , C and C , 2.5 s,
300 mg, 2.1 mmol was added. The mixture was heated
1
w<1 Ž119
.
<
<
Ž117
Sn– C
.<
13
Sn–Me,
J
x
Sn– C s494.8 Hz,
J
at reflux, under N2 stream, with stirring for 2 days. The
rose solution was then allowed to cool and the solvent
w
Ž
.x
s472.3 Hz . IR: 3125 w, 3092 w n C–H , 546s
w
Ž
.
x
w
Ž
.
x
w
Ž
.
Ž
n Sn–C , 229s n Sn–Cl , 179s, 172s d C–Sn–C
was removed with a rotary evaporator. CH2Cl2 50
cm3 was added, the suspension was filtered and the
Ž
.x
.
and d Cl–Sn–Cl .
organic layer was dried on anhydrous Na2 SO4. It was
then filtered and concentrated under reduced pressure.
CH2Cl2 and Et2O were added until a pale-rose precipi-
tate was formed. This was filtered off, washed with
diethyl ether and crystallized twice from CH2Cl2rEt2O
to yield the analytical sample 4. Yield: 39%, m.p.
[
(
)
(
)]
2.2.2. Trimethylbis 1-methylimidazole tin IV iodide
( )
2
3
Ž
.
Ž
.
To a stirred refrigerated 08C THF solution 50 cm
of La 130 mg, 0.46 mmol , sodium iodide 693 mg,
Ž
.
Ž
.
4.6 mmol was added under N2 stream. The mixture
was stored at 08C and stirred for 12 h and the solution
was stored in freezer overnight. The solvent was re-
moved with a rotary evaporator, CH2Cl2 50 cm was
added, the suspension was filtered and the organic layer
was dried on anhydrous Na2 SO4. It was then filtered
Ž
139–1408C Found: C, 30.4; H, 5.1; N, 12.5. Calc. for
.
C11H22ClN4O4.5Sn: C, 30.3; H, 5.1; N, 12.8% . NMR
1
3
2
4
5
Ž
.
Ž
.
Ž
.
CDCl3 : H, d 7.91, 7.04, 6.96 s, H , H and H ,
Ž
.
Ž
.
w<2 Ž119
.<
3.85 s, 1-Me , 3.1 br, H2O , 0.72
J
Sn–H s
2
<
Ž117
.
<
x
68.3 Hz,
J
Sn–H s65.8 Hz, s, SnMe . IR: 3250br
w
Ž
.
x
w
Ž
.
x
w
Ž
.
x
,
and concentrated under reduced pressure. Diethyl ether
n O–H , 3123 w n C–H , 1100br, 618 m n ClO4
3
Ž
.
w
Ž
.
x
w
Ž
.x
20 cm was added; the solution was left in freezer for
547 m n Sn–C , 165s, 160s d C–Sn–C .
1 day. A yellow precipitate was formed, which was
filtered off, washed with petroleum etherrdiethyl ether
and shown to be compound 2. Yield: 45%, m.p. 107–
[
(
)
(
)]
2.2.5. Chlorotributyl 1-methylimidazole tin IV
P
(
) ( )
H2 O
5
Ž
Ž
.
1108C Found: C, 29.1; H, 4.8; N, 12.2. Calc. for
To a stirred refrigerated 08C diethyl ether solution
3
100 cm of La 1.00 g, 12.2 mmol , C4 H9 3SnCl
.
Ž
Ž
.
Ž
. Ž
.
C11H21N41SnI: C, 29.0; H, 4.6; N, 12.3% . NMR
2
4
5
Ž
.
Ž
.
Ž
.
CDCl3 : H, d 7.78, 6.92 s, H , H and H , 3.80 s,
990 mg, 3.0 mmol was added under N2 stream. The
2
.
w<2 Ž119
.
<
<
Ž117
Sn–H s
.<
1-Me , 0.89
J
Sn–H s66.0 Hz,
J
mixture was stored at 08C and stirred for 12 h; the
solution was stored in freezer overnight. The solvent
was removed with a rotary evaporator and diethyl
etherrpetroleum ether 1:1 were added until an oil was
formed, which was separated from the solution. The
x
63.1 Hz, s, SnMe . IR: 3105 w, 3085 w, 3070 w
w
Ž
.
x
w
Ž
.x
n C–H , 554s, 546s n Sn–C .
[
(
)
( )]
2.2.3. Trimethylbis 1-methylimidazole tin IV nitrate
( )
3
oily residue was washed with diethyl etherrpetroleum
3
Ž
.
Ž
.
To a stirred refrigerated 08C dry ethanol solution
ether 1:1 3=20 cm , dried in vacuo to constant
3
Ž
.
Ž
.
Ž
.
Ž
.
100 cm of CH3 3SnCl 598 mg, 3.0 mmol , silver
weight 208C, ca. 0.1 Torr and shown to be compound
5. Yield: 55% Found: C, 44.8; H, 8.1; N, 6.4. Calc. for
C16 H35ClN2OSn: C, 45.1; H, 8.3; N, 6.6% . NMR
CDCl3 : H, d 7.6, 7.1, 6.9 br, H , H and H , 3.72
s, 1-Me , 2.4 br, H2O , 1.9–1.1 m, SnBu , 0.90 t,
SnBu . IR: 3400br n O–H , 3102 w n C–H , 602br,
Ž
.
Ž
nitrate 1.02 g, 6.0 mmol was added under N2 stream.
The mixture was stored at 08C and stirred for 3 h. The
.
1
2
4
5
Ž
Ž
.
Ž
.
solvent was removed with a rotary evaporator, CH2Cl2
3
n
Ž
.
.
Ž
.
Ž
.
Ž
50 cm was added, the suspension was filtered and the
n
.
w
Ž
.
x
w
Ž
.x
organic layer was dried on anhydrous Na2 SO4. It was
then filtered and concentrated under reduced pressure.
w
Ž
.x
508 m n Sn–C .
3
Ž
.
The precipitate was dissolved in diethyl ether 100 cm
and La 985 mg, 12.0 mmol was added. A colorless
precipitate was formed immediately, which was filtered
off after 3 h, washed with diethyl ether and shown to be
Ž
.
[
(
)
(
)]
2.2.6. Bromotributyl 1-methylimidazole tin IV
H2 O
P
(
) ( )
6
Compound 6 was prepared similarly to compound 5.
Ž
Ž
compound 3. Yield: 46%, m.p. 130–1348C Found: C,
33.5; H, 5.5; N, 17.7. Calc. for C11H21N5O3Sn: C,
33.9; H, 5.4; N, 18.0% . NMR CDCl3 : H, d 7.67,
6.98 s, H , H and H , 3.78 s, 1-Me , 0.67
Yield: 65% Found: C, 40.6; H, 7.4; N, 6.2. Calc. for
.
C16 H35BrN2OSn: C, 40.9; H, 7.5; N, 6.0% . NMR
CDCl3 : H, d 7.49, 7.06, 6.89 s, H , H and H ,
3.71 s, 1-Me , 2.2 br, H2O , 1.8–1.5 m, SnBu ,
1.5–1.2 m, SnBu , 0.90 t, SnBu . IR: 3430br n O–
1
1
2
4
5
.
Ž
.
Ž
.
Ž
.
.
2
4
5
n
Ž
.
J
Ž
.
Ž
.
Ž
.
Ž
2
w<2 Ž119
.
<
<
Ž117
Sn–H s65.8 Hz, s,
.<
n
n
Ž
.
Ž
.
w Ž
J
Sn–H s68.3 Hz,
x
w
Ž
.x
.
x
w
Ž
.
x
w
Ž
.x
SnMe . IR: 3112 w n C–H , 1366 m, 1348 m
H , 3104 w n C–H , 600sh, 508 m n Sn–C .
w
Ž
.
x
w
Ž
.
x
w Ž
n NO3 , 549 m n Sn–C , 180 m, 175s, 160s d C–
.
x
[
(
)
(
)]
Sn–C .
2.2.7. Tributylbis 1-methylimidazole tin IV iodide P
(
) ( )
H2 O
7
[
(
T r im e th y lb is 1 - m e th y lim id a -
Ž
.
2 . 2 . 4 .
To a stirred refrigerated 08C diethyl ether solution
3
a
)
(
)]
(
Ž
)
( )
4
0.5
Ž
.
Ž
. Ž
.
Ž
zole tin IV perchlorateP H2 O
50 cm of L 500 mg, 6.1 mmol , C4 H9 3SnI 635
3
.
Ž
.
A dry ethanol solution 50 cm of compound 1 200
mg, 0.7 mmol was introduced into a 250 cm round-
bottomed flask fitted with a condenser, and NaClO4
mg, 1.5 mmol was added under N2 stream. The mix-
ture was stored at 08C and stirred for 12 h; the solution
was stored in freezer overnight. A colorless precipitate
3
.

(
)
348
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
was formed, which was filtered off, washed with diethyl
ether and shown to be compound 7. Yield 16%, m.p.
bottomed flask fitted with a condenser and sodium
iodide 2.40 g, 16.0 mmol was added. The mixture was
heated at reflux, under N2 stream, with stirring for 2
Ž
.
Ž
55–588C Found: C, 40.4; H, 6.9; N, 9.1. Calc. for
.
C20 H41IN4OSn: C, 40.1; H, 6.9; N, 9.3% . NMR
days. It was then allowed to cool and the solvent was
1
2
4
5
3
Ž
.
Ž
.
.
Ž
.
CDCl3 : H, d 7.49, 7.05, 6.91 s, H , H and H ,
removed with a rotary evaporator. CH2Cl2 50 cm
n
Ž
.
Ž
.
Ž
3.71 s, 1-Me , 3.1 br, H2O , 1.8–1.5 m, SnBu ,
1.5–1.2 m, SnBu , 0.91 t, SnBu . IR: 3400br n O–
H , 3130sh, 3079sh n C–H , 600sh, 523sh, 513s
was added, the suspension was filtered and the organic
layer was dried on anhydrous Na2 SO4. It was then
filtered and concentrated under reduced pressure. Di-
ethyl ether was added until a brown precipitate was
formed. This was filtered off, washed with diethyl ether
and crystallized twice from diethyl ether to yield the
analytical sample 11. Yield 14%, m.p. 192–1958C
n
n
Ž
.
Ž
Ž
.
w Ž
.
x
w
.x
w
Ž
.
x
w
Ž
.x
n Sn–C , 161s, 154s d C–Sn–C .
[
(
)
(
)] ( )
2.2.8. Chlorotriphenyl 1-methylimidazole tin IV
8
Compound 8 was prepared similarly to compound 7.
Ž
Ž
Yield: 95%, m.p. 133–1358C Found: C, 56.2; H, 4.6;
Found: C, 21.2; H, 3.2; N, 9.7. Calc. for
.
N, 6.0. Calc. for C22 H21ClN2 Sn: C, 56.5; H, 4.5; N,
C10 H18 I2 N4Sn: C, 21.2; H, 3.2; N, 9.9% . NMR
Ž
Ž
1
1
2
4
2
4
5
.
Ž
.
Ž
.
Ž
.
6.0% . NMR CDCl3 : H, d 7.0, 6.9 br, H , H and
CDCl3 : H, d 8.3, 7.5, 7.0 br, H , H and H , 3.83
w<3
Ž
.<
2
.
w<2 Ž119
.
<
<
Ž117
.<
5
.
Ž
.
H , 3.69 s, 1-Me , 7.8–7.6, 7.5–7.3
62.5 Hz, m, SnPh ; C, d 34.3 s, 1-Me 121.0, 128.5,
137.2 s, C , C and C , 129.2 Cor tho , 130.1
J Sn–H s
s, 1-Me , 1.74
J
Sn–H s91.8 Hz,
J
Sn–H
13
x
Ž
.
x
w
Ž
.x
s87.9 Hz, s, SnMe . IR: 3111 w n C–H , 562 m
2
4
5
Ž
.
Ž
.
w
Ž
.x
n Sn–C .
4
3
Ž
<
Ž
.
<
.
Ž
<
Ž
.<
J Sn–C s14.5 Hz, Cpara , 136.7
J Sn–C s
;
119Sn, d y178.6. IR:
.
[
(
2.2.12. Diperchloratedimethylbis 1-methylimida-
)] (
.
Ž
47.1 Hz, Cmeta , 141.5br Ci pso
3158 w, 3132 w, 3110 w, 3063 w n C–H , 459s, 446
)
(
)
zole tin IV 12
w
Ž
.x
Compound 12 was prepared similarly to compound
w
Ž .x w Ž .x w Ž
.x
m
d Ph , 277s n Sn–C , 226s, n Sn–Cl , 202s,
Ž
4. Yield 48%, m.p. 1988C dec Found: C, 23.9; H, 4.0;
w
Ž
.
Ž
.x
176s d C–Sn–C and d Cl–Sn–Cl .
N, 10.1. Calc. for C11H22Cl2 N4O9Sn: C, 24.3; H, 4.1;
1
.
Ž
.
Ž
N, 10.3% . NMR acetone : H, d 8.17, 7.27, 7.17 s,
[
(
)
(
)]
2.2.9. Dichlorodimethylbis 1-methylimidazole tin IV
2
4
5
.
Ž
.
w<2
H , H and H , 3.79 s, 1-Me , 0.66 J Sn–H s82.6
Ž
.<
( )
9
To a stirred diethyl ether solution 50 cm of La
. Ž .
1.00 g, 12.2 mmol , CH3 2 SnCl2 670 mg, 3.0 mmol
3
x
w
Ž
.x
Hz, s, SnMe . IR: 3134 w n C–H , 1095 m, 1080sh,
Ž
.
w
Ž
.
x
w
Ž
.x
618 m n ClO4 , 570sh, 552 m n Sn–C , 181s, 174s
Ž
.
Ž
w
Ž
.x
d C–Sn–C .
was added at room temperature. A colorless precipitate
was formed immediately, which was filtered off after 3
h, washed with diethyl ether and shown to be compound
[
(
)(
2.2.13. Dinitratedimethyl aquo 1-methylimida-
)
(
)] ( )
zole tin IV 13
Ž
9. Yield 95%, m.p. 200–2018C Found: C, 31.2; H, 4.9;
Compound 13 was prepared similarly to compound
N, 14.5. Calc. for C10 H181Cl2 N4 Sn: C, 31.3; H, 4.7; N,
Ž
4. Yield 30%, m.p. 1708C dec Found: C, 19.4; H, 3.8;
2
.
Ž
.
Ž
14.6% . NMR CDCl3 : H, d 8.18, 7.52, 6.94 s, H ,
N, 14.7. Calc. for C6 H14 N4O7Sn: C, 19.3; H, 3.8; N,
.
Ž
.
w<2 Ž119
Sn–H s107.8
13
.<
4
5
H and H , 3.77 s, 1-Me , 1.25
J
1
2
.
Ž
.
Ž
15.0% . NMR acetone : H, d 8.66, 7.60, 7.50 s, H ,
2
<
Ž117
. x Ž
Sn–H s102.9 Hz, s, SnMe ; C, d 34.7 s,
2 4 5
<
Hz,
J
4
5
.
Ž
.
Ž
.
H and H , 4.05 s, 1-Me , 3.0 br, H2O , 0.87, 0.86
.
Ž
.
Ž
1-Me , 121.1, 128.2, 138.6 s, C , C and C , 22.4 s,
w<2
Ž
.
<
Ž
x
w
Ž
.x
J Sn–H s90 Hz, s, SnMe . IR: 3300br n O–H ,
Sn–Me ; 119Sn, d y260.3. IR: 3156 w, 3136 w, 3125
.
w
.
x
w
Ž
.x
3147 w n C–H , 1350br, 1304br, n NO3 , 585 m,
w
Ž
w
.
x
w
Ž
.
x
w
Ž
.x
w n C–H , 567 m n Sn–C , 236s n Sn–Cl , 178s,
w
Ž
.x
575 m, 547 m, n Sn–C .
Ž
.
Ž
.x
150s d C–Sn–C and d Cl–Sn–Cl .
[
(
)(
2.2.14. Chlorodimethylbis aquo 1-methylimida-
[
(
)
(
)]
2.2.10. Dibromodimethylbis 1-methylimidazole tin IV
)
(
)] ( )
zole tin IV tetraphenyl borate 14
(
)
10
Compound 10 was prepared similarly to compound
9. Yield 95%, m.p. 221–2238C Found: C, 25.8; H, 4.1;
N, 11.9. Calc. for C10 H181Br2 N4Sn: C, 25.4; H, 3.8; N,
11.8% . NMR CDCl3 : H, d 8.32, 7.55, 6.97 s, H ,
Compound 14 was prepared similarly to compound
4. Yield 18%, m.p. 154–1568C Found: C, 57.8; H, 5.8;
N, 4.4. Calc. for C34 H42 BClN4O2 Sn: C, 58.0; H, 5.8;
N, 4.5% . NMR CDCl3 : H, d 8.0, 6.8 br, H , H
Ž
Ž
1
2
4
.
Ž
.
Ž
2
.
Ž
.
Ž
5
.
Ž
.
Ž
.
Ž
and H , 7.8–6.8 m, BPh , 3.52 s, 1-Me , 1.6 br,
w<2 Ž119
. x
Sn–H s65 Hz, s, SnMe . IR: 3642
4
5
.
Ž
.
w<2 Ž119
Sn–H s100.3
.<
H and H , 3.81 s, 1-Me , 1.49
J
.
<
H2O , 0.72
J
2
<
Ž117
. x
Sn–H s95.7 Hz, s, SnMe . IR: 3131 w,
<
Hz,
J
w
Ž
.x
m, 3609 w, 3582 m, 3360br n O–H , 3126 w, 3108
w
Ž
.
x
w
Ž
.
x
w
Ž
.x
3120 w n C–H , 565s n Sn–C , 189 m n Sn–Br ,
w
Ž
w
.
x
w
Ž
.x
w, 3051 w n C–H , 541s n Sn–C , 446 m, 440sh
d Ph , 193s n Sn–Cl .
w
Ž
.
Ž
.x
165s, 152s d C–Sn–C and d Br–Sn–Br .
w
Ž
.
x
Ž
.x
[
(
)
(
)]
[
(
)
2.2.11. Diiododimethylbis 1-methylimidazole tin IV
2 .2 .1 5 .
D im e th y lb is 1 - m e th y lim id a -
] (
(
)
)
(
)
11
zole tin IV diisothiocyanate 15
Compound 15 was prepared similarly to compound
4. Yield 65%, m.p. 159–1608C Found: C, 33.4; H, 4.3;
3
Ž
.
Ž
A dry THF solution 100 cm of compound 9 768
mg, 2.0 mmol was introduced into a 250 cm round-
3
.
Ž

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
349
[
(
)
(
)]
N, 19.3. Calc. for C12 H18 N6S2 Sn: C, 33.6; H, 4.2; N,
2.2.20. Dibromodibutylbis 1-methylimidazole tin IV
P H2 O
1
2
4
.
Ž
.
Ž
(
)
( )
20
0.5
19.6% . NMR CDCl3 : H, d 8.1, 7.5, 7.2 br, H , H
.
Ž
.
w<2 Ž119
.<
5
and H , 3.83 s, 1-Me , 0.94
J
Sn–H s110.3
Compound 20 was prepared similarly to compound
9. Yield 75%, m.p. 127–1298C Found: C, 33.9; H, 5.7;
2
<
Ž117
.
<
x
Ž
Hz,
J
Sn–H s105.5 Hz, s, SnMe . IR: 3150 w,
w
Ž
.
x
w
Ž
.x
3132 w, 3113 w n C–H , 2046s n NCS , 581s
n Sn–C , 181s d C–Sn–C .
N, 9.6. Calc. for C16 H31Br2 N4O0.5Sn: C, 34.0; H, 5.5;
1
2
w
Ž
.
x
w
Ž
.x
.
Ž
.
Ž
N, 9.9% . NMR CDCl3 : H, d 8.4, 7.7, 7.1 br, H ,
H4 and H , 3.78 s, 1-Me , 2.44 br, H2O , 1.94 t,
5
.
Ž
Ž
.
Ž
.
Ž
n
n
n
.
.
Ž
.
SnBu , 1.70–1.40 m, SnBu , 1.24 ps, SnBu , 0.8
[
(
)
(
)]
2.2.16. Dichlorodiethylbis 1-methylimidazole tin IV
n
Ž
w
.
w
Ž
Ž
.x
t, SnBu . IR: 3400br n O–H , 3142 w, 3106 w
(
)
16
Compound 16 was prepared similarly to compound
9. Yield 88%, m.p. 165–1688C Found: C, 34.8; H, 5.6;
Ž
.
x
w
.x
n C–H , 611 m, 558 w n Sn–C .
Ž
[
(
)
( )]
N, 13.5. Calc. for C12 H212Cl2 N4Sn: C, 35.0; H, 5.4; N,
2.2.21. Diiododibutylbis 1-methylimidazole tin IV
2
.
Ž
.
Ž
(
21
)
13.6% . NMR CDCl3 : H, d 8.20, 7.55, 6.94 s, H ,
4
5
.
Ž
.
w<2 Ž119
.<
H and H , 3.77 s, 1-Me , 1.75
J
x
Sn–H s97.9
Compound 21 was prepared similarly to compound
11. Yield 14%, m.p. 96–988C Found: C, 29.2; H, 4.8;
N, 8.3. Calc. for C16 H30 I2 N4Sn: C, 29.5; H, 4.6; N,
2
<
Ž117
.
<
w<3
119Sn–
Ž
J
Ž
Hz,
J
Sn–H s93.5 Hz, q, SnEt , 1.13
3
.
<
<
Ž117
.
<
Ž
x
H s180.3 Hz,
J
Sn–H s172.3 Hz, t, SnEt . IR:
1
2
w
.
.
x
w
Ž
.x
.
Ž
.
Ž
3140 w, 3121 w, 3110 w n C–H , 534s n Sn–C ,
8.6% . NMR CDCl3 : H, d 8.04, 7.34, 6.95 s, H ,
5
n
H4 and H , 3.78 s, 1-Me , 2.03 t, SnBu , 1.7–1.5
w
Ž
.
x
w
Ž
Ž
.x
.
Ž
.
.
Ž
Ž
.
221s n Sn–Cl , 175s d C–Sn–C and d Cl–Sn–Cl .
n
n
n
Ž
.
.
Ž
.
m, SnBu , 1.34 ps, SnBu , 0.88 t, SnBu . IR: 3121
w
Ž
x
w
Ž
.
x
w Ž
w n C–H , 548 m n Sn–C , 177s, 168s d C–Sn–
[
(
)
(
)]
2.2.17. Dibromodiethylbis 1-methylimidazole tin IV
17
.
x
C .
(
)
Compound 17 was prepared similarly to compound
9. Yield 81%, m.p. 174–1768C Found: C, 28.5; H, 4.5;
Ž
[
(
)
(
)]
2.2.22. Dichlorodiphenylbis 1-methylimidazole tin IV
22
(
)
N, 10.9. Calc. for C12 H221 Br2 N4Sn: C, 28.8; H, 4.4; N,
2
.
Ž
.
Ž
11.2% . NMR CDCl3 : H, d 8.34, 7.64, 6.94 s, H ,
Compound 22 was prepared similarly to compound
9. Yield 94%, m.p. 213–2168C Found: C, 47.0; H, 4.5;
.
Ž
.
w<2 Ž119
Sn–H s97.4
.<
4
5
Ž
H and H , 3.77 s, 1-Me , 1.94
J
x
2
<
Ž117
.
<
w<3
Ž
Hz,
J
Sn–H s93.1 Hz, q, SnEt , 1.08
J
119Sn–
N, 10.8. Calc. for C20 H22Cl2 N4Sn: C, 47.3; H, 4.4; N,
3
11.0% . NMR CDCl3 : 1H, d 8.0–7.9, 7.5–7.1
.
<
<
Ž117
.
<
x
.
Ž
.
H s187.5 Hz,
J
Sn–H s179.2 Hz, t, SnEt . IR:
w<3
Ž
.
<
x
Ž
2
4
w
Ž
.
x
w
Ž
.x
3138 w, 3111 w n C–H , 525 m n Sn–C , 163s
J Sn–H s108 Hz, m, SnPh , 7.35, 6.95 s, H , H
5
w
Ž
.
x
w
Ž
.
Ž
.x
.
Ž
.
n Sn–Br , 144s d C–Sn–C and d Br–Sn–Br .
and H , 3.81 s, 1-Me . IR: 3158 w, 3139 w, 3127 w,
w
Ž
.
x
x
w
Ž
.
x
w
Ž
Ž
.x
3060 w n C–H , 463s d Ph , 286s n Sn–C , 238s,
w
Ž
.
w
.
228s n Sn–Cl , 211s, 182s, 167s d C–Sn–C and
[
(
)
( )]
2.2.18. Diiododiethylbis 1-methylimidazole tin IV
18
Ž
.x
d Cl–Sn–Cl .
(
)
Compound 18 was prepared similarly to compound
11. Yield 72%, m.p. 172–1758C Found: C, 24.1; H,
Ž
[
(
)
(
)]
2.2.23. Diiododiphenylbis 1-methylimidazole tin IV
23
(
)
3.8; N, 9.0. Calc. for C12 H22 I2 N4Sn: C, 24.2; H, 3.7;
1
.
Ž
.
Ž
N, 9.4% . NMR CDCl3 : H, d 8.06, 7.41, 6.93 s,
Compound 23 was prepared similarly to compound
11. Yield 69%, m.p. 190–1948C Found: C, 35.0; H,
2
4
5
.
Ž
.
w<2 Ž119
Sn–H s
.<
Ž
H , H and H , 3.78 s, 1-Me , 2.02
J
2
<
Ž117
. x
Sn–H s74.5 Hz, q, SnEt , 1.20
3
<
78.1 Hz,
J
3.4; N, 7.8. Calc. for C20 H22 I2 N4Sn: C, 34.8; H, 3.2;
w<3 Ž119
.
<
<
Ž117
Sn–H s167.5 Hz,
.<
Ž
1
2
4
.
Ž
.
Ž
J
Sn–H s175.2 Hz,
J
N, 8.1% . NMR acetone : H, d 8.37 s, H , H and
5
x
w
.x
.
Ž
.
Ž
.
t, SnEt . IR: 3133 w, 3114 w, 3105 w n C–H , 515 m
n Sn–C , 175s, 160s d C–Sn–C .
H , 8.0–7.6, 7.5–7.0 m, SnPh , 3.95 s, 1-Me . IR:
3151 w, 3131 w n C–H , 459s d Ph , 287s n Sn–
C , 195s, 177s, 158s n Sn–I .
w
Ž
.
x
w
Ž
.x
w
Ž
.
x
w
Ž
.
x
w Ž
.
x
w
Ž
.x
[
(
)
( )]
2.2.19. Dichlorodibutylbis 1-methylimidazole tin IV
(
) ( )
P H2 O 19
[
(
)
(
)]
2.2.24. Trichloromethylbis 1-methylimidazole tin IV
24
(
)
Compound 19 was prepared similarly to compound
Ž
9. Yield 70%, m.p. 115–1188C Found: C, 40.0; H, 6.7;
Compound 24 was prepared similarly to compound
9. Yield 96%, m.p. 3408C dec Found: C, 27.2; H, 4.0;
Ž
N, 11.2. Calc. for C16 H32Cl2 N4OSn: C, 39.5; H, 6.6;
1
.
Ž
.
Ž
N, 11.5% . NMR CDCl3 : H, d 8.18, 7.50, 6.95 s,
N, 13.7. Calc. for C9 H15Cl3N4Sn: C, 26.7; H, 3.7; N,
1
H2, H4 and H , 3.78 s, 1-Me , 2.94 br, H2O ,
5
2
.
Ž
.
Ž
.
.
Ž
.
Ž
13.9% . NMR acetone : H, d 8.35, 7.42, 7.24 br, H ,
n
n
4
5
Ž
.
Ž
.
Ž
.
Ž
.
w<2 Ž119
.<
1.86–1.72 m, SnBu , 1.66–1.46 m, SnBu , 1.25 ps,
SnBu , 0.8 t, SnBu . IR: 3400br n O–H , 3130 w,
3111 w n C–H , 552 m n Sn–C , 230s n Sn–Cl ,
185s d C–Sn–C and d Cl–Sn–Cl .
H and H , 3.88 s, 1-Me , 1.10
J
Sn–H s101.2
2
n
n
<
Ž117
.
<
x
.
Ž
.
w
Ž
.x
Hz,
J
Sn–H s96.4 Hz, s, SnMe . IR: 3124 w
w
Ž
.
x
w
Ž
.
x
w
Ž
.x
w
Ž
.
x
w
Ž
.
x
w Ž
n C–H , 565 m, 526 m n Sn–C , 287s, 277s n Sn–
w
Ž
.
Ž
.x
.
x
w
Ž
.
Ž
.x
Cl , 203s, 175s d C–Sn–C and d Cl–Sn–Cl .

(
)
350
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
[
(
)
( )]
[
(
)(
2.2.25. Trichlorobutylbis 1-methylimidazole tin IV
25
2.2.29.
D im ethyl 1-m ethylim idazole 1,10-
(
)
)
(
)]
(
)
phenanthroline tin IV diperchlorate 29
3
Ž
.
Compound 25 was prepared similarly to compound
9. Yield 95%, m.p. 152–1598C Found: C, 32.1; H, 4.9;
To a stirred diethyl ether solution 100 cm of
Ž
Ž
Ž
.
1,10-phenanthroline
92 m g, 0.5 m m ol ,
138 mg, 0.25 mmol was
a
w
Ž
. Ž
.
Ž
.
2 x
.
N, 12.5. Calc. for C12 H211Cl3N4Sn: C, 32.3; H, 4.7; N,
L
CH3 2 Sn ClO4
2
2
.
Ž
.
Ž
12.5% . NMR CDCl3 : H, d 8.45, 7.6, 6.89 s, H ,
added at room temperature. The colorless precipitate
became immediately pink; it was filtered off after 1 day,
washed with diethyl ether and shown to be compound
29. Yield 87%, m.p. 207–2098C Found: C, 35.4; H,
3.6; N, 9.5. Calc. for C18 H17Cl2O8 N4Sn: C, 35.4; H,
H4 and H , 3.77 s, 1-Me , 2.0–1.8 m, SnBu , 1.7
5
n
.
Ž
.
.
Ž
.
n
n
n
Ž
.
Ž
Ž
.
br, SnBu , 1.30 s, SnBu , 0.85 t, SnBu . IR: 3142
w
Ž
.
x
w
Ž
.
x
w Ž
Ž
w, 3123 w n C–H , 598 m n Sn–C , 266s n Sn–
Cl , 194s, 180s d C–Sn–C and d Cl–Sn–Cl .
.
x
w
Ž
.
Ž
.x
.
Ž
.
Ž
.
3.3; N, 9.2% . NMR CDCl3 : d 9.27 m, Phen , 8.35
Ž
.
Ž
.
Ž
.
d, Phen , 7.88 s, Phen , 7.75 m, Phen , 7.98, 7.19,
[
(
)
(
)]
2.2.26. Trichlorophenylbis 1-methylimidazole tin IV
2
4
5
Ž
.
.
Ž
.
Ž
7.02 s, H , H and H , 3.85 s, 1-Me , 1.15 br,
(
)
26
Compound 26 was prepared similarly to compound
9. Yield 88%, m.p. 184–1858C Found: C, 35.9; H, 3.8;
w
Ž
.x
.
x
w
Ž
.x
SnMe . IR: 3155 w n C–H , 1085s, 623s n ClO4 ,
570 m, 553 m n Sn–C .
w
Ž
Ž
N, 12.1. Calc. for C14 H17Cl3N4Sn: C, 36.0; H, 3.7; N,
1
.
Ž
.
12.0% . NMR acetone : H, d, 8.50, 8.35, 7.55, 7.45
2.3. Crystallography
2
4
5
Ž
.
Ž
.
Ž
br, H , H and H , 7.84 d, SnPh , 7.35–7.15 m,
SnPh , 3.91, 3.87 s, 1-Me . IR: 3150 w, 3128 w
n C–H , 462s, 454s d Ph , 180s, 161s d C–Sn–C
.
Ž
.
x
w
Ž
.
x
w
Ž
.
w
Ž
.
[
(
)
(
)] ( )
2.3.1. Chlorotriphenyl 1-methylimidazole tin IV
8
Ž
.x
and d Cl–Sn–Cl .
A summary of the experimental conditions and solu-
tion of the structure is reported in Table 1. Atomic
coordinates and isotropic equivalent thermal parameters
are reported in Table 2. Colorless well-formed crystals
of the adduct were obtained from the slow evaporation
of an ether solution. A preliminary crystallographic
study was carried out by inspection of oscillation and
Weissenberg photographs, leading to the assignment of
[
(
)
(
)]
2.2.27. Dibromodimethyl 1,10-phenanthroline tin IV
(
)
27
To a stirred diethyl ether solution 100 cm of
1,10-phenanthroline
3
Ž
.
Ž
.
213 mg, 1.2 mmol ,
a
w
Ž
. Ž
. x Ž .
CH3 2 SnBr2 280 mg, 0.6 mmol was added at
L
2
room temperature. The colorless precipitate became im-
mediately pale pink; it was filtered off after 1 day,
washed with diethyl ether and shown to be compound
27. Yield 95%, m.p. 258–2608C, Found: C, 34.6; H,
Ž
the crystal system as triclinic space group P1 after
.
refinement . A crystal with approximate dimensions of
0.4=0.4=0.2 mm was mounted on a Syntex P21
Ž
diffractometer, equipped with a sealed Mo tube 45 kV,
3.0; N, 6.0. Calc. for C14 H14 Br2 N2 Sn: C, 34.4; H, 2.9;
.
1
25 mA and a graphite monochromator. The orientation
.
Ž
.
Ž
.
N, 5.7% . NMR CDCl3 : H, d 9.70 br, Phen , 8.53
matrix and accurate lattice parameters were obtained by
least squares refinement of 15 centered reflections in the
range 4.958F2uF22.388; 11 255 reflections were then
collected in the range 3.08F2uF658. The data were
Ž
.
Ž
.
Ž
.
J
Ž
d, Phen , 8.01 s, Phen , 7.89 m, Phen , 2.47 br,
2
.
w<2 Ž119
.
<
<
Ž117
.<
Sn–H
H2O , 1.39
J
Sn–H s111.4 Hz,
x
w
Ž
.x
s106.5 Hz, s, SnMe . IR 3116 w, 3044 w n C–H ,
w
Ž
.x
570s n Sn–C .
Ž
.
then corrected for decay f10% and for Lorentz and
w x
polarization effects. A semiempirical 6 absorption cor-
[
{
(
)
}
(
Ž
.
2.2.28. Bis diiododiethyltin IV tris 1,10-phenanthro-
)] (
rection was applied on the basis of c-scan of the 5–10
)
line 28
To a stirred diethyl ether solution 100 cm of
reflection, the transmission factor was found to vary
between 0.75 and 1.0. The data were then merged
together giving 10 913 reflections with an Rint of 0.55%.
The structure was solved by direct methods by using
3
Ž
.
Ž
.
150 mg, 0.8 mmol ,
1,10-phenanthroline
a
w
Ž
. Ž
. x Ž .
C2 H5 2 SnI2 264 mg, 0.4 mmol was added at
L
2
w x
room temperature. The yellow precipitate became black;
it was filtered off after 1 day, washed with diethyl ether
and shown to be compound 28. Yield 85%, m.p. 139–
the SIR92 program 7 ; all the non-H atoms in the
asymmetric unit were located at this stage, that is two
distinct organotin–imidazole adducts. The structure was
then refined, using the crystallographic program pack-
Ž
1428C Found: C, 38.0; H, 3.2; N, 6.2. Calc. for
C44 H44 I9 N6Sn: C, 37.7; H, 3.2; N, 6.0% . NMR
CDCl3 : H, d 9.75 d, Phen , 8.53 d, Phen , 8.01 s,
Phen , 7.88 m, Phen , 1.98
.
w x
age CRYSTALS 8 , imposing isotropic thermal param-
1
Ž
.
Ž
.
.
Ž
.
Ž
eters for all the atoms and using only the 5705 reflec-
.
Ž
w<2 Ž119
.<
J
<
<
Ž
<
<.
J
Sn–H s93.0 Hz,
tions having Fo G3s Fo ; the R factor after conver-
gence was 0.099. A new refinement was performed
treating thermal vibration anisotropically and the R
factor was lowered to 0.049. At this stage, by means of
a Fourier difference, we were able to locate the H atoms
2
<
Ž117
.
<
x
w<3 Ž119
.<
Sn–H
J
Sn–H s88.1 Hz, q, SnEt , 0.88
3
Sn–H s189.3 Hz, t, SnEt ; 119Sn,
<
Ž117
.
<
x
s198.0 Hz,
J
w
Ž
.x
d y177.7. IR: 3180 w n C–H , 520 m, 509 m
w
Ž
.x
n Sn–C .

Table 1
Crystal data: data collection and refinement of the structure for 1-methylimidazole triphenyltin IV chloride 8 , bis 1-methylimidazole dimethyltin IV dibromide 10 and bis 1-methylimida-
wŽ
.
Ž
.x
Ž . w
Ž
.
Ž
.
x Ž
.
w
Ž
.
Ž
.
x Ž .
zole diethyltin IV diiodide 18
Compound
8
10
18
Formula
Formula weight
C22 H21N2ClSn
467.585
C10 H18 N4 Br2 Sn
472.777
C12 H22 N4 l2 Sn
594.853
Space group
P1
Ž .
9.561 2
P1
Ž .
7.477 2
C2rc
8.041 2
˚
w x
Ž .
a A
˚
w x
Ž .
15.431 7
Ž .
7.425 1
Ž .
15.988 3
b A
˚
w x
c A
Ž .
15.025 6
89.36 4
Ž .
8.057 2
Ž .
14.702 6
w x
Ž .
Ž .
105.16 2
a 8
y
w x
b 8
Ž .
Ž .
112.32 2
Ž .
98.02 2
Ž .
384.9 2
1
2.0398
67.962
226.0
Ž .
105.90 3
94.86 2
w x
g 8
Ž .
85.02 3
y
1883.4 6
3
˚
A
w
x
Ž .
2124 1
4
1.463
13.409
936
Ž .
Vc
Z
4
y3
w
x
Dc g cm
2.0980
46.32
1112.0
y1
Ž
Ž
. w
x
m Mo K a cm
.
F 000
˚
˚
˚
.
Ž
.
Ž
.
Ž
.
Ž
Radiation monochromated
Mo Ka ls0.71069 A
Mo Ka ls0.71069 A
Mo Ka ls0.71069 A
w x
T of data collection K
Scan mode
Scan width 8
Scan speed 8 min
Background:scan ratio
293
293
293
vr2u
vr2u
vr2u
w x
w
0.68 below Ka1, 0.6 above Ka 2
minimums1.502, maximums14.648
0.5
0.68 below Ka 1, 0.6 above Ka 2
minimums1.502, maximums14.648
0.5
0.68 below Ka 1, 0.6 above Ka 2
minimums1.502, maximums14.648
0.5
y1
x
w x
Data collection range 8
h; k; l range
Standards
3.0F2u F65
5.0F2u F55
5.0F2u F60
y12™11, y23™23, 0™21
1 1 0, 2 2 y2, 1 3 1
y9™8, y9™9, 0™10
2 3 0, 1 2 1, 0 4 y2
0™12, 0™23, y21™21
2 2 y3, 2 0 y6, 0 4 4
Ž
.
measured every 97 reflections
Number of unique reflections measured 10913
1780
6076
<
<
Ž< <.
Number of data with Fo G3s Fo
5498
1715
2000
Refinement
Fullymatrix leastysquares on F
469
0.038
0.044
0.988
Fullymatrix least-squares on F
79
0.026
0.030
1.28
Full-matrix least-squares on F
88
0.044
0.054
1.179
Number of parameters refined
Ra
Rbw
Sc goodness of fit
Ž
.
a
Ž
5
<
<
5.
<
<
Rs Ý Fo yk Fc r S Fo .
b
c
2
1r2
w
Ž<
<
<
<.2
<
< x
Rw s Ýw Fo yk Fc r Sw Fo
.
1r2
w
Ž<
<.2
<
<
Ž
.x
Ss Ýw Fo yk Fc r Nobs y Npar
.

(
)
352
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
Table 2
them. The methyl groups were found to be disordered
over several different conformations, the hydrogens were
then modeled on the basis of the most intense peak with
a reasonable geometry. The structure was refined again,
by fixing the thermal isotropic parameters for the
hydrogens at 30% greater than the value of the bonded
carbons, and refining the coordinates using the riding
model; the R value for the 469 parameters was 0.040.
A final least squares refinement was then performed
Atomic fractional coordinates and isotropic equivalent thermal pa-
Ž
.
wŽ
.
rameters with e.s.d. in parentheses for 1-methylimidazole triph-
x Ž .
Ž
.
enyltin IV chloride
Atom xra
0.29449 4
8
2
yrb
0.20873 2
zrc
0.77475 3
0.7010 1
0.8423 3
0.9230 4
0.9434 3
0.8695 5
0.8077 4
1.0271 5
0.6599 4
0.5715 5
0.4990 5
0.5134 6
0.5992 6
0.6713 4
0.8867 4
0.9358 4
Ua
A
˚
Ž .
eq
Ž
.
Ž
.
Ž .
Ž .
Ž .
Ž .
0.0558 2
Sn 1a
Ž
.
Ž .
0.2248 5
Ž .
Ž .
Ž .
0.0912 7
Cl 1a
0.3829 2
0.0768 1
Ž
.
Ž .
Ž .
Ž .
Ž .
0.064 2
N 1a
0.3409 3
Ž
.
Ž .
Ž .
Ž .
Ž .
0.080 3
C 2a
0.2968 8
Ž .
0.3664 4
Ž
.
Ž .
Ž .
Ž .
0.070 2
N 3a
0.2413 6
0.4430 3
Ž
.
.
.
.
.
.
Ž .
Ž .
Ž .
Ž .
0.082 3
C 4a
C 5a
C 6a
C 7a
C 8a
C 9a
C 10a
C 11a
C 12a
C 13a
C 14a
C 15a
C 16a
C 17a
C 18a
C 19a
0.1252 7
0.4674 4
after optimizing the weighting scheme on the basis of
2
Ž
Ž .
Ž .
Ž .
Ž .
0.066 2
0.1174 6
0.4058 3
<
<
the distribution of the mean of w D as function of Fo
Ž
Ž .
Ž .
Ž .
Ž .
0.112 4
0.289 1
Ž .
0.4915 5
Ž
and sin url. A robust-resistant weighting scheme in
Ž
Ž .
Ž .
Ž .
0.060 2
0.1070 6
0.2394 4
.
order to properly handle possible outliers in the data set
Ž
Ž .
Ž .
Ž .
Ž .
0.088 3
0.1171 9
0.2597 5
w
x
w x
9,10 based on Cheybishev polynomials 11 with coef-
ficients a1 s0.381, a2 s0.320, a3 s0.181 was used.
Ž
Ž .
Ž .
Ž .
Ž .
Ž .
0.116 5
y0.010 1
0.2770 6
Ž
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Ž .
Ž .
Ž .
0.105 3
y0.145 1
0.2773 5
Ž
Ž .
Ž .
Ž .
Ž .
0.090 3
y0.1547 8
0.2587 5
The final R factor was 0.038.
Ž
Ž .
Ž .
Ž .
Ž .
0.071 2
y0.0320 7
0.2398 4
All the refinement steps reached convergence, with-
out showing any difficulties, or correlations between
parameters greater than 0.8. The final r.m.s. shift was
below 0.01; the minimum and maximum Dr were
y0.37 and 0.75, both near the tin atoms.
Ž
Ž .
Ž .
Ž .
Ž .
0.057 2
0.2579 6
0.1362 3
Ž
Ž .
Ž .
Ž .
Ž .
0.076 3
0.1617 7
Ž .
0.1686 4
Ž
Ž .
Ž .
Ž .
0.094 4
0.1316 9
0.1179 6
1.0032 5
1.0234 5
0.9774 6
0.9092 5
0.7913 4
0.8393 6
Ž
Ž .
Ž .
Ž .
Ž .
0.115 5
0.193 1
0.0355 7
Ž
Ž .
Ž .
Ž .
Ž .
0.126 5
0.291 1
Ž .
0.3225 8
0.0028 6
Ž
Ž .
Ž .
Ž .
0.085 3
0.0520 4
All the refinements were made taking the anomalous
scattering into account, but no correction was intro-
duced for the extinction. Scattering factors and anoma-
lous contributions were taken from the International
Ž
Ž .
Ž .
Ž .
Ž .
0.063 2
0.4961 6
0.2637 4
Ž
Ž .
Ž .
Ž .
Ž .
0.098 4
C 20a
C 21a
C 22a
C 23a
0.6228 7
0.2166 6
Ž
Ž .
Ž .
Ž .
Ž .
0.755 1
Ž .
0.252 1
Ž .
0.8570 8
Ž .
0.140 6
Ž .
0.143 7
0.136 6
Ž .
0.103 4
Ž
0.761 1
0.333 1
0.828 1
Ž
Ž .
Ž .
Ž .
Ž .
Ž .
0.641 2
0.3831 7
0.7790 8
0.7607 6
w
x
w x
Tables 12 . Program PARST 13 was used for some
geometrical and crystallographic calculations.
Ž
Ž .
Ž .
C 24a
0.5031 9
0.3477 6
Ž
.
Ž .
Ž .
Ž .
Ž .
0.0532 2
Sn 1b
0.30105 4
0.25882 2
0.27020 3
0.1328 1
0.3902 3
0.3881 4
0.4635 3
0.5182 4
0.4722 4
0.4846 5
Ž
.
Ž .
Ž .
Ž .
Ž .
0.0749 5
Cl 1b
0.1096 2
0.3346 1
[
(
)
(
)]
2.3.2. Dibromodimethylbis 1-methylimidazole tin IV
Ž
.
Ž .
Ž .
Ž .
Ž .
0.058 2
N 1b
0.4812 5
0.1786 3
(
)
10
A summary of the experimental conditions and solu-
Ž
.
Ž .
Ž .
Ž .
Ž .
0.060 2
C 2b
0.6102 6
0.1411 3
Ž
.
Ž .
Ž .
Ž .
Ž .
0.067 2
N 3b
0.6710 5
0.0908 3
tion of the structure is reported in Table 1. Atomic
coordinates and isotropic equivalent thermal parameters
are reported in Table 3. Crystals of the compound were
grown from a colorless dichloromethanerdiethyl ether
Ž
.
.
.
.
.
.
Ž .
Ž .
Ž .
Ž .
0.070 2
C 4b
C 5b
C 6b
C 7b
C 8b
C 9b
C 10b
C 11b
C 12b
C 13b
C 14b
C 15b
C 16b
C 17b
C 18b
C 19b
0.5780 7
0.0960 4
Ž
Ž .
Ž .
Ž .
Ž .
0.067 2
0.4618 6
0.1492 4
Ž
Ž .
Ž .
Ž .
Ž .
0.095 3
0.8174 7
0.0419 5
Ž
Ž .
Ž .
Ž .
Ž .
0.059 2
0.4712 6
0.2740 4
0.2072 4
0.1370 5
Ž
Ž .
Ž .
Ž .
Ž .
0.085 3
0.4965 7
0.2229 5
Ž
.
solution 1:1 by slow evaporation. A colorless crystal
with approximate dimensions of 0.50=0.30=0.30 mm
was mounted on an automatic four circle diffractometer,
Ž
Ž .
Ž .
Ž .
Ž .
0.610 1
Ž .
0.2367 7
Ž .
0.0977 6
Ž .
0.113 4
Ž .
0.126 5
Ž
.
.
.
.
.
.
.
.
.
.
.
0.699 1
0.3002 8
0.1293 8
Ž
Ž .
Ž .
Ž .
Ž .
0.125 5
0.675 1
0.3511 7
0.1963 8
0.2357 6
0.3663 4
0.4468 5
0.5096 6
0.4923 7
0.4155 7
0.3515 5
Ž
Ž .
Ž .
Ž .
Ž .
0.095 3
0.5634 8
0.3389 5
Ž
.
equipped with a sealed Mo tube 45 kV, 25 mA . The
crystal system was found to be triclinic, and accurate
Ž
Ž .
Ž .
Ž .
Ž .
0.066 2
0.2776 7
0.3574 4
Ž
Ž .
Ž .
Ž .
Ž .
0.087 3
0.3881 9
0.3691 4
Ž
Ž .
Ž .
Ž .
Ž .
0.109 4
0.373 1
0.4315 5
Ž
Ž .
Ž .
Ž .
Ž .
0.132 6
0.244 2
0.4830 5
Table 3
Ž
Ž .
Ž .
Ž .
Ž .
0.132 5
0.132 1
0.4750 6
Atomic coordinates and isotropic equivalent thermal parameters for
Ž
Ž .
Ž .
Ž .
Ž .
0.097 3
0.1489 9
0.4128 5
Ž
.
Ž
. Ž .
dibromobis 1-methylimidazole dimethyltin IV 10
Ž
Ž .
Ž .
Ž .
Ž .
0.054 2
0.1805 6
0.1472 3
0.2615 3
0.2510 4
Ž
Ž .
Ž .
Ž .
Ž .
0.070 3
C 20b
C 21b y0.0463 8
C 22b
C 23b
C 24b
0.0324 6
0.1577 4
2
˚
Ž
.
Atom xra
Ž .
yrb
0.0000
zrc
0.000
Ua
A
Occupation
eq
Ž
.
Ž .
Ž .
Ž .
Ž .
0.0877 5
Ž .
0.2472 5
Ž .
0.089 3
Ž .
0.089 3
Ž .
0.078 3
Ž .
0.061 2
Sn 1
Ž .
0.000
0.0266 1.0000
Ž
.
.
.
Ž .
0.0194 9
0.0040 5
0.2506 5
Ž .
Ž .
Ž .
Br 1 y0.27908 5
0.19939 5 y0.11291 5 0.0433 1.0000
Ž
Ž .
Ž .
Ž .
Ž .
0.1663 9
y0.0075 4
0.2598 4
0.2662 4
Ž . Ž .
Ž . Ž .
N 1 y0.1613 4 y0.2463 4 y0.2983 4 0.0343 1.0000
Ž
Ž .
Ž .
0.0629 3
0.2474 6
Ž . Ž . Ž . Ž .
N 3 y0.2538 4 y0.5322 4 y0.5163 4 0.0356 1.0000
aU is defined as the mean of the principal axes of the thermal
C 2 y0.1584 5 y0.4297 5 y0.3304 5 0.0358 1.0000
Ž . Ž . Ž . Ž .
Ž . Ž . Ž . Ž .
eq
ellipsoid.
C 4 y0.3235 6 y0.4100 6 y0.6089 5 0.0447 1.0000
Ž . Ž . Ž . Ž .
C 5 y0.2663 6 y0.2341 6 y0.4744 6 0.0435 1.0000
Ž . Ž . Ž . Ž .
Ž . Ž . Ž . Ž .
C 6 y0.2822 7 y0.7391 5 y0.6032 6 0.0496 1.0000
C 7 0.1740 6 0.1539 5 y0.1002 6 0.0399 1.0000
of the imidazoles, whereas they were introduced by
˚
aU is defined as the mean of the principal axes of the thermal
Ž
.
model ds0.96 A for the phenyl rings, because no
eq
hydrogen with a reasonable geometry was found for
ellipsoid.

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
353
Table 4
cell parameters were obtained by least-squares refine-
ment of 26 reflections with 118F2uF308; the space
group was found to be P1.
A total of 1926 reflections was collected with y9F
hF8, y9FkF9 and 0FlF10; no decay was ob-
served during the data collection. The c-scan of the
Ž
Atomic coordinates and isotropic equivalent thermal parameters with
e.s.d. in parenthesis for diidodobis 1-methylimidazole diethyltin IV
.
Ž
.
Ž
.
Ž
.
18
Atom xra
Ž .
2
Ua
A
Occupation
˚
Ž
.
yrb
zrc
eq
Ž . Ž . Ž . Ž .
0.01229 7 0.14348 3 0.09482 3 0.0741 2 1.0000
I 1
Ž .
Ž .
0.0456 2 0.5000
Sn 1 0.2500
N 1 0.2565 8 0.3434 3 0.1250 3
0.2500
0.0000
Ž
.
reflection y1, 6, 3 gave a minimum and a maximum
transmission factor equal to 0.99993 and 1.10217, re-
spectively; the data were then corrected for the absorp-
Ž . Ž .
Ž .
Ž .
Ž .
0.057 2 1.0000
Ž . Ž . Ž . Ž .
Ž .
0.059 2 1.0000
N 3 0.2366 7 0.3953 3 0.2621 3
Ž . Ž . Ž . Ž .
Ž .
0.056 2 1.0000
C 2 0.2167 8 0.3266 4 0.2084 4
Ž . Ž . Ž . Ž .
w x
tion using a semi-empirical method 6 .
Ž .
0.066 2 1.0000
C 4 0.292 1 0.4581 4 0.2102 5
Ž . Ž . Ž . Ž .
Ž .
0.065 2 1.0000
C 5 0.304 1 0.4262 4 0.1265 4
C 6 0.205 1 0.3990 6 0.3593 4
The structure was solved by direct methods by using
Ž . Ž . Ž . Ž .
Ž .
0.084 3 1.0000
w x
the SIR92 program 7 , all of the 9 non-hydrogen atoms
Ž . Ž . Ž .
Ž .
Ž .
C 7 0.039 1 0.3168 6 y0.0629 6 0.094 4 1.0000
in the asymmetric unit were found at this level.
The hydrogen atoms were located by means of a
Fourier difference map, performed by using the CRYS-
Ž . Ž . Ž . Ž . Ž .
C 8 0.002 3 0.327 2 y0.159 2 0.117 7 0.5038
Ž . Ž . Ž . Ž . Ž .
C 9 0.030 3 0.395 2 y0.078 2 0.111 7 0.4962
aU is defined as the mean of the principal axes of the thermal
w x
eq
TALS package 8 , and an isotropic refinement of all
ellipsoid.
the atoms gave R equal to 0.0860. The structure was
then anisotropically refined with the hydrogens refined
located by means of Fourier difference maps performed
Ž
as riding U was fixed at 30% greater than that of the
iso
w x
by using the CRYSTALS package 8 , with the excep-
.
bonded carbons . A final refinement was performed
tion of the last carbon of the ethyl which was rather
disordered, showing up in two different positions in the
Fourier map. After a last isotropic refinement, the hy-
w
x
after an optimization of the weighting scheme 9,10 ,
where an optimized truncated Cheybishev polynomial
with coefficients a1 s0.730, a2 s0.285, a s0.551,
x3
˚
drogens were imposed by a model with ds1.0 A and
w
a4 s0.0635, a5 s0.138 was employed 11 , refining
the extinction parameter as well. The R factor was
0.026 at the end of the last refinement cycle, with a
maximum r.m.s. shift equal to 0.00.
U
fixed as 30% greater than the bonded carbons. The
iso
structure was then anisotropically refined with the hy-
drogens refined as riding. In the first cycles of the
refinement, the two possible positions of the terminal
carbon of the ethyl were kept fixed while their percent-
age of occupation was refined; then these occupations
were kept fixed at the two positions refined isotropi-
cally. A final refinement was performed after an opti-
[
(
)
(
)] ( )
2.3.3. Diiododiethylbis 1-methylimidazole tin IV 18
A summary of the experimental conditions and solu-
tion of the structure is reported in Table 1. Atomic
coordinates and isotropic equivalent thermal parameters
w
x
mization of the weighting scheme 9,11 using an opti-
mized truncated Cheybishev polynomial with coeffi-
cients a1 s0.549, a2 s0.446, a3 s0.290. The R factor
was equal to 0.044 at the end of the last refinement
cycle, with a maximum r.m.s. shift equal to 0.02.
w
are reported in Table 4. Pale yellow crystals of di-
Ž
.
Ž
.x
iododiethylbis 1-methylimidazole tin IV were ob-
tained by slow evaporation from an ether solution. A
crystal with approximate dimensions of 0.3=0.4=0.4
mm was mounted on a Syntex P21 four-circle diffrac-
tometer and accurate lattice parameters were obtained
by least-squares refinement of 40 reflections collected
in the range 108F2uF258. A total of 6076 unique
reflections was collected in the range 58F2uF558 by
an vr2u scan data collection; of these 2000, with I
3. Results and discussion
3.1. Synthesis, reactiÕity and properties of the organ-
(
)
otin IV complexes
Ž .
greater than 3s I , were used in the subsequent refine-
Ž
.
Interaction between various organotin IV com-
Ž
.
ment. A continuous decay f20% of the standard
reflections intensity was observed and a correction was
made; the data were also corrected for Lorentz and
polarization effect. The c-scan of three different reflec-
a
Ž
.
pounds and an excess 1-methylimidazole L in an
organic solvent diethyl ether or THF at 08C or at room
temperature gave the compounds 1–2, 5–10, 16, 17, 19,
Ž
.
Ž
.
Ž .
20, 22, and 24–26 Fig. 2a , in accordance with Eq. 1 :
Ž
.
tions 0 y4 4, y1 y3 6, 1 y5 7 gave a minimum
and a maximum transmission factor equal to 0.81 and
1.00, respectively; the data were then corrected for the
solvent
x La q R SnX
PzH O ™
Ž
.
Ž
.
n
4yn
2
w x
absorption using a semi-empirical method 6 .
= La
R SnX
PzH2O
1
Ž .
Ž
. x Ž
.
The structure was solved finding first the Sn and I
atoms, by a Patterson map using the Shelxs86 program
n
4yn
RsMe, Et, Bun or Ph; XsCl or Br, ns1, 2 or 3;
Ž
w
x
14 . At this stage, an isotropic refinement gave an R
equal to 17.74. The other non-hydrogen atoms were
xs1 or 2; zs0, 1r2 or 1
.

(
)
354
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
With the exception of the triorganotin chloride and
BPhy4 or NCSy occurred when ethanol solutions of
Ž
bromide complexes 1, 5, 6, and 8 for which a ligand to
NaClO4, AgNO3, NaBPh4 or KSCN were added to an
ethanol solution of 9, and the complexes 12, 13, 14, and
15 were produced. They were characterized and shown
to have different stoichiometries. 2:1 adducts were ob-
.
metal ratio of 1 to 1 was observed 2:1 adducts were
always obtained. This fact further confirms that the
Ž
.
possibility of obtaining 2:1 adducts with triorganotin IV
chloride and bromide acceptors is limited to imidazole
type donors able to involve the halide group in a
hydrogen bonding network. On the other hand the 1-
methylimidazole is able to displace the iodide from the
tained when the counter ion was ClO4y or NCSy Fig.
Ž
.
2a , whereas a 1:1 ligand to metal ratio was found in the
Ž
.
nitrato and tetraphenylborato derivatives Fig. 2c . In
the last case, the substitution of the Cly with BPhy4 is
only partial: one Cly group remains bonded to the
coordination sphere of the tin center, yielding the ionic
a
w
Ž
.
x
Ž
.
Ž
.
derivatives
L
2 R3Sn IPzH2O 2, 7 .
tin IV center together with two molecules of water.
Substitution of Cly with Iy was always successful.
Conversion of the chlorides into iodides produced the
derivatives 2, 11, 18, 21, and 23. The disproportionation
If the reaction between La and CH3 3SnCl was
Ž
.
carried out in dry ethanol solution containing AgNO3,
a
w
Ž
. Ž . x Ž .
CH3 3Sn NO3 3 was formed.
2
the complex
L
The substitution of the Cly with ClO4y was achieved
when an ethanol solution of NaClO4 was added to an
ethanol solution of 1. The substitution with ClO4y, NOy3 ,
of the tin IV halides previously observed in the deriva-
tives of 4-phenylimidazole 1 , in accordance with
Kocheshkov’s reaction 15 , did not occur in this case.
Ž
.
w x
w
x
Ž
.
Fig. 2. Structures proposed for organotin IV derivatives of 1-methylimidazole.

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
355
Various degrees of hydration have been found from
0.5, as in compound 4, to 2, as in compound 14. In fact,
coordinated by bridging iodide groups and monodentate
Phen seems to be likely, also on the basis of literature
Ž
.
Ž
.
w
x
tin IV and organotin IV complexes often absorb
molecules of water from atmosphere and solvent and
they are not easy to recrystallize. All the attempts to
eliminate the presence of water from our complexes
failed.
data 16–19 .
3.2. IR data
By comparison with the data reported for other
Ž
.
All the diorgano- and triorgano-tin IV derivatives
are moderately soluble in chlorinated solvents, acetone
and DMSO, and insoluble in diethyl ether, ethanol and
water. The monoorganotin IV adducts are generally
less soluble in all the solvents commonly used. These
compounds are stable also when exposed to moisture
for a long time, whereas upon prolonged standing at
1208C, or in acetone and chloroform solutions, organ-
Ž
.
organotin IV complexes containing N-donor ligands
w
x
20,21 , we suggest the following assignments for
adducts 1–29.
Ž
.
3.2.1. Ligand absorptions
In the 3150–2950 cmy1 region, the ligand exhibits
weak bands typical of C–H stretching due to a pseu-
doaromatic ring, and in the region 1600–1500 cmy1
some more intense absorptions due to the ring breathing
Ž
.
otin IV oxides and hydroxides are often recovered.
Ž
.
The triorganotin IV adducts 1–8 are often unstable
also in the solid state. When 1, 5, and 8 are exposed to
air for 4–10 h, they decompose in accordance with the
following equation:
w
x
mode 22 . These bands do not shift markedly upon
coordination to tin, suggesting a weak influence of the
complexation on the absorptions within the donor.
2 La R SnClz La 2R SnCl qR4Sn
Complex 10 reacts with 1,10-phenanthroline yielding
2
Ž .
Ž
.
Ž
.
3
2
2
3.2.2. Sn–C stretching frequencies
Ž
.
In the triorganotin IV derivatives 2 and 5–7 two
strong or medium absorptions are always observed in
the 600–500 cmy1 region. They are due to nŽasym. and
nŽsym. Sn–C stretching vibrations and are consistent
with an essentially trigonal pyramidal arrangement of
organic groups with a marked deviation from planarity.
The appearance of only a single Sn–C stretching bond
w
Ž
.Ž
.
x
the hexacoordinate 1:1 adduct Phen CH3 2 SnBr2 27,
resulting from the displacement of both the imidazole
ligands. This kind of reactivity is due to the chelating
ability of Phen, which predominates despite the greater
s-basicity of imidazole. On the other hand, if the start-
Ž
.
ing tin IV was coordinated by a good leaving group
at ca. 550 cmy1, in the spectra of trimethyltin IV
complexes 1 and 3, is taken to imply a C3n symmetry of
such as ClO4y
L
CH3 2 Sn ClO4
a
Ž
.
Ž
w
Ž
. Ž
.
Ž
.
2 x .
12 , we ob-
2
served a partial substitution of imidazole and complete
w
x
displacement of ClO4y from the coordination sphere,
the C3-skeleton 23–26 .
Only a single Sn–C stretching vibration was ob-
with formation of the mixed-ligands complex
a
Ž
.
served in the spectra of the diorganotin IV derivatives
9–11 and 13–23 in accordance with a trans-octahedral
w
Ž
.Ž
.Ž . xŽ . Ž .
Phen CH3 2 Sn ClO4 29 Fig. 3 . A different
2
L
result was obtained when Phen reacted with
a
a
w
x
configuration of the two alkyl groups 27,28 . In the
spectrum of derivative 24, two medium absorptions at
565 and 525 cmy1, respectively, were found. In this
case, the presence of two different isomers is likely.
It was noted that on changing the halide groups
w
Ž
. Ž
. x
C2 H5 2 SnI2 : in this case the donor L was
L
2
displaced completely and a compound with a 3:2 stoi-
chiometry Phen C2 H5 2 SnI2
Ž
w
Ž
.
3Ä
Ž
.
42
x
.
28 afforded. Sev-
eral attempts to crystallize this compound in suitable
form for the X-ray analysis failed. In absence of struc-
tural data, it is very difficult to indicate with a certainty
the coordination environment of the tin center; however
Ž
.
Ž
.
linked to tin IV little shift of the n Sn–C was ob-
served.
Ž
.
a di- or oligo-nuclear structure with the tin IV atom
3.2.3. Sn-halide stretching frequencies
Ž
.
In the triorganotin IV derivative 1, we observed the
tin chloride stretching frequency as strong absorption at
229 cmy1. This further supports the non-ionic nature of
this compound. The absorption is markedly shifted with
Ž
.
respect to that indicated for the starting triorganotin IV
w
x
chloride 29 .
A similar shift was observed in the case of the
Ž
.
w
x
Ž
.
triphenyltin IV adduct 8 30 . The tin IV chloride
Ž
.
stretching frequencies in the di- and tri-halidetin IV
derivatives fall as strong or medium broad bands at ca.
230 and 260 cmy1, respectively. These bands are low-
ered by 90–130 cmy1 with respect to those found in the
Fig. 3. Structure proposed for the ionic mixed ligand complex 29.

(
)
356
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
The NOy3 group in 3 was found to be ionic. The
Ž
.
w x
starting tin IV reagents 29 . The tin bromide stretch-
ings bands, where detected, are shifted with respect to
strong absorptions at 1366 and at 1348 cmy1 are similar
tin IV chloride by 40–60 cmy1, in accordance with
trends previously observed 29 .
Ž
.
w
x
to those indicated for ionic nitrato compounds 38 .
In derivative 15, the NCSy group could be coordi-
nated to tin through the nitrogen or the sulfur: we
w
x
propose that complex 15 is N-bonded, because it ex-
y1
Ž
.
hibits a single sharp d NCS near 480 cm
and the
3.2.4. Other absorptions
n NCS below 2050 cmy1. These absorptions are com-
parable with those found in other isothiocyanate com-
Ž
.
Ž
It is not possible to assign with certainty the d Cl–
.
Ž
.
Ž
.
Ž
.
Sn–Cl , d C–Sn–C , d C–Sn–Cl , r Sn–C3 and
w
x
Ž
.
plexes 39–42 .
r Sn–Cl which generally fall in the region 200–120
3x
cmy1 29 , because in these complexes these bands are
too close to resolve.
w
3.3. Mossbauer results
¨
Several weak bands, which appeared in the spectra of
all the complexes in the region 300–400 cmy1 and were
absent in the spectra of the free donor and acceptor
could be tentatively assigned to n Sn–N 31,32 . Fur-
ther support for this assumption derives from the obser-
vation that all the other donor absorptions, in the 3200–
400 cmy1 region, do not markedly shift upon complex-
ation.
The experimental Mossbauer parameters, isomer shift
¨
y1
y1
Ž
.
Ž
.
IS mm s , nuclear quadrupole splitting QS mm s
y1
Ž
.
w
x
Ž
.
are listed in
and full width at half-height G" mm s
Table 5.
The IS value is typical of quadrivalent tin in
w
x
organometallic derivatives 43 ; the examined com-
pounds are all potentially octahedral, except for deriva-
tive 1 to which a trigonal bipyramidal arrangement can
be assigned. In the exa-coordinated series, the IS value
increases with the covalent character of the tin-ligand
bonds; however, it is lower for Me2 SnCl2 adduct 9 than
Et2 SnCl2 derivative 16, in keeping with the larger
The perchlorato complex 4 was found to be ionic: a
single broad absorption at ca. 1100 and a sharp band at
620 cmy1 were observed 33 , whereas derivative 12
showed a more complex pattern, analogous to that
found in derivatives containing unidentate perchlorato
groups. In this case, in the absence of X-ray crystal data
we are unable to indicate the nature of the two ClO4y
groups; however, we exclude a completely ionic struc-
w
x
hyperconjugation of the methyl group bound to the tin
a
wŽ
.
x
atom. The IS values of
L
2 BuSnCl3 25 compares
Ž
.
well with literature values of monoalkyltin IV halides
Ž
.
w x
43 . The QS value of derivatives 9, 16–18, and 25 is
ture with the tin IV tetracoordinated, such as
a
w
Ž
. Ž
.
xqq
CH3 2 Sn
w
yx2
ClO4
L
.
indicative of an octahedral configuration of the tin
2
We use the combination band n1 qn4y1of free NO3
atom; in Alk SnX2 adducts a trans alkyl arrangement
is inferred 44 . Using the Parish relationship between
the QS and C–Sn–C bond angle, u, their values, lying
in the range 160–1758, were calculated 44 .
Derivatives 10 and 19 show a greatly asymmetric
doublet Fig. 4 . The deconvolution of the spectrum
points out the presence of two Mossbauer components,
w
x
w
2 x
34 , which appears in the 1800–1700 cm region, for
structural diagnosis: in the spectrum of 13, upon coordi-
nation, this absorption splits in two bands and the
separation is of the same order of magnitude as that
w
x
found in unidentate NOy3 derivatives 35–37 . For this
reason, we suggest for this compound the structure
shown in Fig. 2c.
w
x
Ž
.
¨
Ž
.
the one split line attributed to the octahedral trans-R2
Table 5
Selected Mossbauer data
¨
Compound
y1
y1
y1
Ž
.
Ž
.
Ž
.
Ž
.
Number
Ž .
ISa,b mm s
QSb mm s
G"b mm s
C–Sn–Cc deg
a
wŽ .Ž
.
x
L
CH3 3SnCl
1
Ž .
1.27
1.21
1.42
0.03
1.39
1.48
1.61
1.46
0.04
0.84
3.46
3.92
3.94
0.89
0.94
0.96
0.93
0.97
1.00
0.99
0.96
0.92
1.01
a
wŽ . Ž
.
.
x
x
L
CH3 2 SnCl2
CH3 2 SnBr2
CH3 2 SnBr2 singlet
C2 H5 2 SnCl2
C2 H5 2 SnBr2
C2 H5 2 Snl2
C4 H9 2 SnCl2 PH2O
C4 H9 2 SnCl2 PH2O singlet
9
164
165
2
a
wŽ . Ž
Ž
10
.
L
2
a
wŽ . Ž
.
x Ž
.
L
2
a
wŽ . Ž
.
x
Ž
16
Ž
17
Ž
18
Ž
19
.
.
.
.
L
4.03
3.86
3.92
3.36
175
160
164
0.96
2
a
wŽ . Ž
.
x
L
2
a
wŽ . Ž x
.
L
2
a
wŽ . Ž
.
x
x
L
2
a
wŽ . Ž .
.
Ž
L
2
a
wŽ . Ž
.
x
Ž .
25
L
C4 H9 SnCl3
1.85
2
a With respect to an R.T. spectrum of CaSnO3.
b "0.01 mm sy1
.
c
y1
w
x
Calculated by using the literature partial quadrupole splittings: Alk sy1.01 mm s
.

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
357
a
wŽ . Ž
.
x Ž
.
Fig. 4. Mossbauer spectrum of
¨
deconvoluted components.
L
CH3 2 SnBr2 10 . Experimental points shown by crosses, continuous lines show the fitted curve and the
2
Ž
.
tin atom, the other unsplit line to SnO2 , obtained
probably because of the presence of moisture.
whereas it is only partial in the di- and mono-
Ž
.
organotin IV derivatives. We also found that in this
kind of compounds the dissociation is not very depen-
dent on the concentration of the solution: for example r
for compound 1 is 0.53 at concentration 0.84 mg gy1
and 0.58 at 2.35 mg gy1 of CHCl3.
The QS value of adduct 1 is in consonance with a
trigonal bipyramidal structure with axial chlorine and
w
x
nitrogen atoms 45 .
Ž
.
The diorganotin IV diiodide adducts 18, 21, and 23
3.4. BehaÕiour in solution
exhibit a value of conductivity in acetone typical of a
Ž
.
1:1 electrolyte, whereas the dimethyltin IV diiodide 11
shows a value in the same solvent typical of a 2:1
electrolyte: this compound is also strongly dissociated
in CHCl3 solution. On the basis of this evidence, we
hypothesized an ionic nature in solution of complex 11
Ž
.
The conductivity measurements Table 6 were car-
ried out in acetone solution for all the soluble com-
pounds and in CH2Cl2 and DMSO only for selected
derivatives, whereas the molecular weight determina-
tions were performed in chloroform solution only on
sufficiently soluble and stable adducts. The data show
that triorganotin IV halide adducts 1–3 and 5–8, and
the mono- and di-organotin IV choride and bromide
complexes are not electrolytes in acetone and CH2Cl2 ,
Ž .
in accordance with Eq. 4 :
La CH SnI2 qn solvent z La CH 2Sn
Ž
.
Ž
.2Ž
.
Ž
.
Ž
.2Ž
.
3
3
2
Ž
.
= solvent qqq2 I
4
y
Ž
.
Ž .
n
Ž
even if they dissociate in CHCl3 solution rsratio
Compounds 13 and 15 are partly ionized: similar
behaviour has been previously observed for analogous
between the vaporimetric molecular weight and formula
.
weight lying in the range 0.30–0.58 , in accordance
with the Eq. 3 , which indicates ligand loss in solution.
Ž
.
organotin IV complexes containing imidazole-type
Ž .
w
x
donors 1,5 .
La x R SnX4yn z La xy1R SnX qLa
Ž
.
Ž
.
n
n
4yn
3.5. NMR data
zRnSnX4yn qxLa
Several trends emerged: for example we noted that
3
Ž .
1
The H NMR spectra of the donor La and of the
Ž
.
organotin IV complexes 1–29 were recorded in CDCl3,
and for some derivatives in acetone due to poor solubil-
ity in the former solvent.
Ž
Ž ..
dissociation Eq. 3 is dependent on the nature of the
halide and organic substituent: r has the greatest value
when XsCl, and the smallest when XsI. The dissoci-
Ž
.
The spectra of the triorganotin IV complexes 1–7
Ž
.
ation is complete in the triorganotin IV adducts,
indicate a nearly complete dissociation into the starting

(
)
358
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
Table 6
a
Ž
.
Selected conductivity and molecular weight measurements of organotin IV derivatives of L
Compound
Conductivitya
Molecular weightb
Solvent
Concentration
L
Formula weight Molecular weight
r
Concentration
a
wŽ .Ž
.
x
Ž .
1
L
CH3 3SnCl
Acetone 0.79
CH2Cl2 0.53
4.5 281.3
0.8
148
164
0.53 0.84
0.58 2.35
DMSO
Acetone 0.57
CH2Cl2 0.48
1.28
4.4
30.0
4.0
a
wŽ . Ž
.
x
Ž .
2
L
CH3 3Sn I
2
DMSO
Acetone 0.73
CH2Cl2 1.02
0.28
30.2
19.9
3.9
a
wŽ . Ž
.
xŽ
.
Ž .
3
L
CH3 3Sn NO3
2
DMSO
0.96
32.8
145.7
43.4
1.2
8.4
10.3
3.3
a
wŽ . Ž
.
xŽ
.
Ž .
4
L
CH3 3Sn ClO4 P1r2H2O
Acetone 0.82
CH2Cl2 0.79
Acetone 1.10
Acetone 0.52
Acetone 0.35
Acetone 1.02
Acetone 0.73
CH2Cl2 0.95
2
a
wŽ .Ž
.
.
x
Ž .
5
L
C4 H9 3SnCl PH2O
C4 H9 3SnBr PH2O
a
wŽ .Ž
x
Ž .
6
L
a
wŽ . Ž
.
x
Ž .
7
L
C4 H9 3Sn IPH2O
2
a
wŽ .Ž
.
.
x
Ž .
8
L
C6 H5 3SnCl
a
wŽ . Ž
x
x
Ž .
9
L
CH3 2 SnCl2
18.9 383.9
1.0
169
178
208
166
206
215
182
175
216
0.44 0.78
0.46 1.93
0.54 4.10
0.35 0.77
0.44 1.79
0.45 2.49
0.32 0.49
0.31 0.92
0.38 1.98
2
a
wŽ . Ž
.
Ž
Ž
Ž
.
L
CH3 2 SnBr2
10 Acetone 0.69
34.0 472.8
1.4
2
CH2Cl2 0.51
a
wŽ . Ž
.
x
.
L
CH3 2 Snl2
11 Acetone 0.36
186.9 566.8
10.6
2
CH2Cl2 0.07
a
wŽ . Ž
.
Ž
.2 x
.
L
CH3 2 Sn ClO4
12 Acetone 0.82
197.6
10.0
37.7
93.9
65.0
2
CH2Cl2 0.90
DMSO
13 Acetone 0.15
14 Acetone 0.97
CH2Cl2 Insoluble
15 Acetone 1.09
CH2Cl2 0.99
16 Acetone 0.75
0.52
a
wŽ .Ž
.
.
Ž
. Ž
.x
Ž
Ž
.
.
L
CH3 2 Sn NO3 H2O
CH3 2 SnCl H2O BPh4
wŽ .Ž
Ž
2 . xŽ
.
a
L
2
a
wŽ . Ž
.
Ž
. x
Ž
.
L
CH3 2 Sn NCS
60.0
1.7
13.9
26.7
97.1
16.7 486.0
2
2
a
wŽ . Ž
.
x
Ž
Ž
Ž
Ž
.
L
C2 H5 2 SnCl2
2
a
wŽ . Ž
.
x
.
L
C2 H5 2 SnBr2
17 Acetone 0.80
18 Acetone 1.48
19 Acetone 0.47
2
a
wŽ . Ž
.
.
x
.
L
C2 H5 2 Snl2
2
a
wŽ . Ž
x
.
L
C4 H9 2 SnCl2 PH2O
151
146
182
0.31 0.60
0.30 1.00
0.37 2.11
2
a
wŽ . Ž
.
x
Ž
Ž
Ž
.
L
C4 H9 2 SnBr2 P1r2H2O
20 Acetone 0.78
.
29.2
134.1
25.0
0.4
134.1
4.3
2
a
wŽ . Ž
.
x
L
C4 H9 2 Snl2
21 Acetone 0.58
2
a
wŽ . Ž
.
x
.
L
C6 H5 2 SnCl2
22 Acetone 0.98
2
CH2Cl2 1.00
a
wŽ . Ž
.
x
Ž
Ž
.
L
C6 H5 2 Snl2
23 Acetone 0.98
2
CH2Cl2 1.00
a
wŽ
.
x
.
L
2CH3SnCl3
24 Acetone 0.85
27.3 404.3
0.9
175
168
0.43 0.40
0.42 0.45
CH2Cl2 0.78
DMSO
25 Acetone 0.89
26 Acetone 1.01
27 Acetone 0.78
0.51
27.9
18.4
18.3
3.4
a
wŽ . Ž
.
x
x
Ž
Ž
Ž
.
L
C4 H9 SnCl3
2
a
wŽ . Ž
.
.
L
C6 H5 SnCl3
wŽ
2.Ž
.
x
.
Phen CH3 2 SnBr2
CH2Cl2 0.99
0.3
wŽ
. ÄŽ
.
42 x
Ž
Ž
.
Phen C2 H5 2 Snl2
28 Acetone 0.71
23.6
25.8
171.0
12.9
3
CH2Cl2 0.91
a
wŽ .Ž
L
.Ž
.
xŽ
.
.
Phen CH3 2 Sn ClO4
29 Acetone 1.01
2
CH2Cl2 1.01
a
In Vy1 cm2 moly1 at room temperature; concentration is molar concentration =10
3
Ž
.
.
b Temperatures408C, in CHCl3; rsmolecular weightrformula weight; concentration is mg of compoundrg of CHCl3.

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
359
13
Ž
Ž
.
reagents. In fact, the D value difference in chemical
In the C NMR spectra of triorganotin IV com-
n
13
Ž119
. Ž
.
shift for the same type of proton in the free base and in
pounds 1 and 8 the J
of the same order of magnitude of those observed in
pentacoordinate organotin IV compounds and greater
Sn– C ns1, 2, 3 or 4 are
Ž
.
.
its organotin IV complexes is in the range 0.01–0.54
ppm and the tin-proton coupling constants are of the
same order of magnitude as those reported for the
starting triorganotin IV acceptors 46 . However, the D
observed in these derivatives, which is evidence of the
existence of the complexes in solution, is bigger with
respect to those observed in other derivatives containing
imidazole-type donors and triorganotin IV acceptors
1,5 .
Instead, in the spectrum of the triphenyltin IV com-
plex 8, the signals of the ligand are displaced upfield
and the D value is in the range y0.37–y0.09 ppm.
This peculiarity can be explained by considering the
shielding effect exerted on H2, H4 and H5 protons by
aromatic protons of the phenyl rings linked to tin IV ;
the tin-proton coupling constants are greater than that
reported for the starting triorganotin IV acceptor, in
accordance with a partial dissociation of the complex in
CDCl3 solution. Compound 8 shows the 119Sn NMR
absorption at y178.6 ppm; this value is upfield shifted
with respect to that observed for Ph3SnCl in the same
Ž
.
Ž
Ž
.
.
w x
than those in the starting organotin IV derivatives 47 .
Ž
.
w
x
In the spectra of the diorganotin IV complexes 9–23,
the signals of the ligand La are generally displaced to
lower field. The deshielding observed is attenuated at a
position remote from the metal methyl protons . The D
observed is likely due to a s-charge donation from the
N-donor to tin IV acceptor and is evidence of the
existence of the complexes in solution. However, the
magnitude of the tin IV -proton coupling constants for
all these diorganotin IV complexes, even if it is differ-
ent from that reported in literature for the starting
tetracoordinate diorganotin IV halides 48 , is smaller
with respect to that indicated for hexacoordinate undis-
Ž
.
Ž
.
w
x
Ž
.
Ž
.
Ž .
Ž
.
Ž
.
w x
Ž
.
Ž
.
sociated organotin IV complexes containing N-donor
Ž
.
w
x
ligands 49,50 : this suggests a partial dissociation of
our complexes in chlorinate solution in accordance with
the data derived from molecular weight measurements
Table 6 . The 119Sn NMR spectrum of 9 confirms the
Ž
.
Ž119
.
partial dissociation observed: the d
shifted with respect to that found in other completely
Sn is upfield
w
x
solvent 47 .
a
wŽ
. x Ž .
Fig. 5. The molecular structure of
L Ph3SnCl 8 with atom numbering, as used in the crystallographic work.

(
)
360
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
Ž
dissociated azole complexes C. Pettinari and M. Pellei,
unpublished results .
3.6. Crystal structures
.
In the 1H NMR spectrum of 14, the deshielding
observed in the resonance due to H2, H4, and H5
protons of the ligands is the smallest of the
diorganotin IV derivatives investigated; besides the
signal of the CH3 of the imidazole moiety is observed
upfield shifted with respect to the same resonance in the
free donor Dsq0.12 . This trend could be explained
by considering the shielding effect exerted on CH3, H2,
and H4 or H5 by the aromatic protons of BPhy4 counter-
ion.
3.6.1. Diffraction study of L Ph3 SnCl 8
The molecular structure of L Ph3SnCl 8 is shown
in Fig. 5, together with the numbering scheme. Selected
a
[( ] ( )
)
a
w
Ž
.
x
Ž
.
bond distances and angles are reported in Table 7.
a
wŽ
.
x
The crystallographic study of L Ph3SnCl clearly
Ž
shows that two independent molecules A and B here-
Ž
.
.
after are present in the asymmetric units. The coordina-
tion geometry at Sn can be described as a distorted
trigonal bipyramid with nitrogen and halogen in axial
positions and three phenyl groups in equatorial posi-
tions. The distortion from the ideal trigonal bipyramidal
geometry in both the molecules is evident from the
magnitude of the Cl–Sn–N 175.5 1 8 and 175.3 1 8
and Cl–Sn–C bond angles which range from 91.5 2 8
Ž . .
to 95.0 2 8 . Moreover, an almost planar Sn–C3 unit
The diiodide 3:2 complex 28 shows a value of
Ž119
. Ž .
d
Sn typical of pentacoordinate tin IV derivatives,
Ž
Ž . Ž . .
in accordance with a ionic dissociation in solution hy-
pothesized also on the basis of conductivity data. On the
other hand in the solid state, if the phenanthroline were
coordinated in the bidentate fashion, the tin IV atom
should be hepta- or even octa-coordinate; however, in
view of the rarity of these coordination numbers for
R2 Sn IV adducts and on the basis of literature data
16–18 we suggest for compound 28 a hexacoordinate
dinuclear configuration with bridging iodide groups and
at least two monodentate Phen molecules.
Ž
Ž .
Ž
.
Ž
.
ÝC–Sn–C 359.18 and 359.38 in A and B, respectively
is present in the structure, with the tin atom residing
slightly below that plane on the side of the axial chlo-
rine atom, onto the side opposite the attacking nitrogen
atom. This geometry corresponds to an intermediate
stage of the SN 2 reaction pathway of a nucleophilic
Ž
.
w
x
Ž
.
attacked triorganotin IV halide, during its passage from
Table 7
˚
Ž
.
Ž
.
wŽ
.
Ž
.x
Ž
.
Selected interatomic distance A and bond angles deg with e.s.d. in parentheses, for 1-methylimidazole triphenyltin IV chloride 8
Molecule A
Molecule B
Bond lengths
Ž
.
Ž
.
Ž .
2.520 2
2.412 4
Ž . Ž .
Sn 1B –Cl 1B
Sn 1B –N 1B
Ž .
2.546 2
Sn 1A –Cl 1A
Ž
.
Ž
.
Ž .
Ž
.
Ž
.
Ž .
2.372 4
Sn 1A –N 1A
Ž
.
.
Ž
.
Ž .
Ž . Ž .
Sn 1B –C 13B
Ž .
2.122 5
Sn 1A –C 7A
2.134 6
Sn 1B –C 7B
Ž
Ž
.
.
Ž .
Ž
.
Ž
.
.
Ž .
2.148 6
Sn 1A –C 13A
2.134 6
Ž
.
Ž
Ž .
Ž . Ž
N 1B –C 2B
Ž .
2.140 5
Sn 1A –C 19A
Ž
2.126 6
Sn 1B –C 19B
.
Ž
.
.
.
.
.
Ž .
Ž
.
Ž
.
.
.
.
.
Ž .
1.324 7
N 1A –C 2A
1.304 7
Ž
.
Ž
Ž .
Ž . Ž
Ž .
1.374 7
N 1A –C 5A
1.359 7
N 1B –C 5B
Ž
.
Ž
Ž .
Ž
.
Ž
Ž .
1.328 7
N 3A –C 2A
1.328 7
N 3B –C 2B
Ž . Ž
Ž
.
Ž
Ž .
Ž .
1.364 8
N 3A –C 4A
1.360 8
N 3B –C 4B
Ž
.
Ž
Ž
Ž .
Ž
.
Ž
Ž .
1.483 7
N 3A –C 6A
1.455 8
N 3B –C 6B
Ž
.
.
Ž .
Ž . Ž .
Ž .
1.339 8
C 4a –C 5A
1.329 8
C 4B –C 5B
Bond angles
Ž
.
Ž
.
Ž
.
Ž .
175.5 1
93.5 2
Ž . Ž . Ž .
Cl 1B –Sn 1B –N 1B
Cl 1B –Sn 1B –C 7B
Ž .
175.3 1
Cl 1A –Sn 1A –N 1A
Ž
.
Ž
.
Ž
.
Ž .
Ž
.
Ž
.
Ž
.
Ž .
92.1 1
Cl 1A –Sn 1A –C 7A
Ž
.
.
.
.
.
.
Ž
Ž
Ž
Ž
Ž
Ž
.
.
.
.
.
.
Ž
.
Ž .
Ž . Ž . Ž .
Ž .
86.3 2
N 1A –Sn 1A –C 7A
87.6 2
N 1B –Sn 1B –C 7B
Ž
Ž
.
Ž .
Ž
.
Ž
.
Ž
.
Ž .
95.0 2
Cl 1A –Sn 1A –C 13A
94.5 2
Cl 1B –Sn 1B –C 13B
Ž
Ž
.
.
Ž .
Ž . Ž . Ž .
Ž .
89.7 2
N 1A –Sn 1A –C 13A
89.0 2
N 1B –Sn 1B –C 13B
Ž
Ž
Ž .
Ž
.
Ž
.
Ž
.
Ž .
114.4 2
C 7A –Sn 1A –C 13A
115.4 2
C 7B –Sn 1B –C 13B
Ž . Ž . Ž .
Ž
Ž
Ž
.
Ž .
Ž .
91.6 1
Cl 1A –Sn 1A –C 19A
91.5 2
Cl 1B –Sn 1B –C 19B
Ž
.
.
Ž .
Ž
.
Ž
.
Ž
.
.
Ž .
85.8 2
N 1A –Sn 1A –C 19A
84.2 2
N 1B –Sn 1B –C 19B
Ž
.
Ž
.
Ž
Ž .
Ž
.
Ž
.
Ž
Ž .
C 7A –Sn 1A –C 19A
123.7 2
C 7B –Sn 1B –C 19B
125.6 2
Ž .
119.3 2
Ž
.
Ž
.
Ž
.
Ž .
Ž
.
.
Ž
.
Ž
.
C 13A –Sn 1A –C 19A
Ž
Ž
120.0 2
C 13B –Sn 1B –C 19B
.
Ž
Ž
.
.
Ž
Ž
.
.
Ž .
Ž
Ž
.
Ž
.
.
Ž .
128.6 4
Sn 1A –N 1A –C 2A
Sn 1A –N 1A –C 5A
123.5 4
Sn 1B –N 1B –C 2B
Sn 1B –N 1B –C 5B
.
Ž .
Ž . Ž . Ž
Ž .
125.7 4
131.0 4
Ž
.
Ž
.
Ž
.
.
.
.
Ž .
Ž
.
.
Ž
.
Ž
.
.
.
.
Ž .
105.0 4
C 2A –N 1A –C 5A
105.4 5
C 2B –N 1B –C 5B
Ž
.
Ž
.
Ž
Ž .
Ž
Ž
.
Ž
Ž .
107.8 5
C 2A –N 3A –C 4A
105.4 5
C 2B –N 3B –C 4B
Ž
.
Ž
.
Ž
Ž .
Ž . Ž . Ž
Ž .
125.0 6
C 2A –N 3A –C 6A
128.5 6
C 2B –N 3B –C 6B
Ž
.
Ž
.
Ž
Ž .
Ž
.
Ž
.
Ž
Ž .
C 4A –N 3A –C 6A
126.1 6
Ž .
C 4B –N 3B –C 6B
127.1 5
Ž
.
Ž
.
Ž
.
Ž
.
Ž
.
Ž
.
Ž .
N 1A –C 2A –N 3A
112.4 5
N 1B –C 2B –N 3B
111.1 5
Ž
.
Ž
.
Ž
.
.
Ž .
Ž
.
Ž
.
Ž
.
.
Ž .
N 3A –C 4A –C 5A
107.7 5
N 3B –C 4B –C 5B
106.0 5
Ž
.
Ž
.
Ž
Ž .
Ž . Ž . Ž
Ž .
110.1 5
N 1A –C 5A –C 4A
109.1 6
N 1B –C 5B –C 4B

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
361
Ž
.
w
x
a monocapped tetrahedron to an ideal trigonal bipyra-
in another tbp chlorotriphenyltin IV complexes 56,57 .
The values observed are at the top of the ranges ob-
w
x
mid as deduced by Britton and Dunitz 51 .
˚
˚
Ž . Ž .
Ž .
A B . They are longer than the sum of the covalent
Ž
The Sn–N distances are 2.412 4 A A and 2.372 4
served for this kind of fragment 2.475–2.535 A, twelve
˚
Ž .
radii of tin and nitrogen 2.15 A and significantly
shorter than the sum of their van der Waals radii 3.75
A thus indicating a substantial bonding interaction 52 .
The Sn–N bond distances found here are longer with
respect to those observed in diorganotin IV bis im-
idazole complexes 53–55 in accordance with stronger
Lewis acidity of R2 SnX2 with respect to R3SnX accep-
tors. However, the Sn–N distances in 8 are longer also
.
entries in the Cambridge Crystallographic Data Files
˚
Ž
.
w x
58 . There is also a correlation along the Cl–Sn–N axis
Ž
in A and B: as the Sn–N distance becomes shorter, the
˚
.
w x
Sn–Cl one tends to become longer, in accordance with
the Dunitz curve 51 for SnC3 XY ensembles. The
Sn–C bond distances 2.122 5 –2.148 6 A fall within
w
x
˚
.
Ž
.
Ž
Ž
Ž .
Ž .
.
w
x
Ž . w
the range expected for triphenyltin IV structures 56–
x
58 .
The two molecules A and B are significantly differ-
w
Ž
.
Ž . Ž . Ž .
with respect to those in bis 4-phenylimidazole trimeth-
ent: for example in A the Sn 1A –N 1A –C 2A angle
Ž
.
x
w x
Ž
.
Ž
.
Ž
.
yltin IV chloride 1 , in which both the azoles occupy
Ž .
was greater than Sn 1A –N 1A –C 5A , whereas the
Ž
the apical positions. The Sn–Cl bond distances 2.520 2
opposite trend was observed in B; in addition in B the
˚
˚
˚
Ž .
Ž .
.
A in A and 2.546 2 A in B are as long as those found
tin atom was displaced by 0.307 2 A out of the imida-
Table 8
Comparison of selected bond distances and angles in R3SnNX-type compounds
Compounda
Sn–N
Ž .
Sn–X
Ž .
Sn–C
X–Sn–N
Ž .
Ref.
a
wŽ
L
.
x
Ž .
Ž .
Ž .
Ph3SnCl
2.412 4
2.520 2
2.134 6 , 2.134 6 , 2.126 6
Ž . Ž . Ž .
175.5 1
this work
Ž .
Ž .
Ž .
2.372 4
2.546 2
2.122 5 , 2.148 6 , 2.140 5
175.3 1
wŽ
. Ž
Ph3SnCl m-NC 2 Fe CN dmso
2
C,N- Me2 NCH2C6 H4 SnPh2 Br
Ž
.
Ž
. Ž
. x
Ž .
Ž .
Ž . Ž . Ž .
Ž .
w
57
w
60
w
61
x
x
x
2.340 7
2.535 3
2.140 4 , 2.149 4 , 2.144 6
175.5 2
2
2
Ä
4
Ž
.
.
Ž .
Ž
.
Ž .
Ž
.
Ž .
2.511 12
2.630 2
2.115 10 , 2.124 9 , 2.150 12
Ž . Ž . Ž .
171.0 1
t
.
Ž .
Ž .
Ž .
167.2 1
2- Me2 NCHBu C6 H4SnMePhBr
2.552 5
2.6725 9
2.143 5 , 2.142 5 , 2.137 6
Ž .
Ž .
Ž . Ž . Ž .
Ž .
169.4 1
2.482 5
2.6702 7
2.139 5 , 2.122 6 , 2.128 6
Ž
Ž .
Ž .
Ž .
w
62
w
63
w
64
w
65
x
x
x
x
1-Aza-5-stanna-5-Cl–tricycloundecane
2.372 29
Ž .
2.613 7
Ž .
2.169 8
Ž .
180.0 0
w
Ž
.
x
Ž .
Ž
Ž .
Ž .
8- NMe2 -1-naphthyl SnMePhBr
Ž . Ž
2.496 6
2.667 1
2.131 6 , 2.151 6 , 2.144 9
171.5 1
Ä
w
.
.
x
4
Ž .
Ž .
Ž . Ž .
.
Ž .
2- 1- S - Me2 N Et Ph SnMePhBr
2.476 7
2.683 1
2.158 9 , 2.160 10 , 2.127 8
168.9 2
Ž
Ž .
Ž .
Ž . Ž . Ž .
Ž .
172.7 2
N CH2CH2CH2 3SnFdPH2O
2.426 6
2.121 5
2.146 7 , 2.132 9 , 2.145 9
Ž .
Ž .
Ž . Ž . Ž .
Ž .
2.393 5
Ž .
2.115 6
Ž .
2.145 8 , 2.135 8 , 2.126 7
Ž .
174.0 2
Ž
.
Ž
Ž
.
.
Ž .
w
65
w
65
w
65
w
65
w
66
w
66
x
x
x
x
x
x
N CH2CH2CH2 3SnCl hex
2.37 2
2.52 1
2.14 1
180.0 0
Ž
.
Ž .
Ž .
Ž .
Ž .
N CH2CH2CH2 3SnCl mon
2.384 4
2.554 1
2.157 5
179.7 1
180
Ž
.
Ž .
Ž .
Ž .
N CH2CH2CH2 3SnBr
2.28 2
Ž .
2.693 2
Ž .
2.20 1
Ž .
Ž
.
Ž .
N CH2CH2CH2 3SnI
2.375 6
2.896 1
2.152 8
179.6 1
w
Ž
.
Ž
.
x
Ž .
Ž .
Ž
.
Ž .
Ž
.
Ž .
175.4 2
Me2ClSn CH2 Sn NC5H5 ClMe2
Me2Cl N2C3H3 Sn CH2 Sn N2C3H3
ClMe2
2.439 9
2.638 2
2.089 12 , 2.099 8 , 2.148 11
w
Ž
.
Ž
.
Ž
.
Ž
.
.
Ž .
Ž . Ž . Ž
.
.
Ž .
174.6 4
2.459 15
2.578 4
2.114 14 , 2.154 16 , 2.162 20
x
Ž
Ž .
2.603 5
Ž
.
Ž
.
Ž
Ž .
174.6 4
2.453 14
Ž .
2.142 14 , 2.106 18 , 2.132 17
Ž . Ž . Ž .
w
Ž
.Ž
.
x
Ž .
Ž .
w
66
x
Me2ClSn CH2 N2C4 H4 SnClMe2
2.651 6
2.473 2
2.115 7 , 2.128 8 , 2.30 8
Ž . Ž . Ž .
2.129 7 , 2.129 8 , 2.125 8
177.6 2
Ž .
Ž .
Ž .
2.715 6
2.456 2
177.7 1
w
w
w
Ž
.
x Ž
.
Ž
.
Ž .
Ž
.
Ž
.
Ž
.
Ž .
w
66
w
67
w
68
x
x
x
Me2ClSn CH2 SnClMe2 N2C4 H4
2.622 14
2.524 6
2.120 15 , 2.128 18 , 2.184 20
176.2 5
2
Ž
.
Ž
.xy
Ph3SnCl m-CN Ag CN
Ž .
Ž .
Ž . Ž . Ž .
Ž .
2.436 5
2.518 2
2.155 5 , 2.138 4 , 2.151 6
175.5 1
Ž
.
x Ž
.
Ž .
2.55 1
Ž .
2.630 2
Ž . Ž . Ž .
Ž .
168.1 2
8- Me2 N -1-naphthyl - y -menthyl-
2.19 1 , 2.11 2 , 2.13 1
MeSnBr
Ž .
2.55 1
Ž .
2.414 5
Ž .
2.641 2
Ž .
2.6788 8
Ž .
Ž .
Ž .
Ž .
168.1 3
Ž .
171.3 1
2.16 1 , 2.13 1 , 2.18 1
w
Ž
.
x
Ž . Ž .
Ž .
w
69
x
2- 4,4-Me2-2-oxazoline -5-MePh
MePhSnBr
2.148 6 , 2.128 7 , 2.125 6
w
Ž
.
x
Ž .
2.580 8
Ž .
2.451 3
Ž .
Ž .
2.12 1 , 2.13 1 , 2.13 3
Ž .
Ž .
168.4 2
w
70
w
71
x
x
Sn 2-C6 H4 N5NPh Ph2Cl
2.560 4
2.445 2
2.130 4 , 2.141 4 , 2.129 4
167.0 1
w
Ž
.
x
Ž .
Ž .
Ž . Ž . Ž .
Ž .
2- 4,4-Me2-2-oxazolinyl -3-thienyl
Ph2 SnCl
Ž .
2.463 7
Ž .
2.693 1
Ž .
Ž .
Ž .
Ž .
169.9 2
2.525 7
2.469 3
2.10 1 , 2.12 1 , 2.128 9
w
w
x
Ž .
Ž .
Ž
.
.
Ž
Ž
.
.
Ž
Ž
.
.
Ž .
170.5 2
w
w
x
x
BrPh2 SnCH2-1,2,4-triazole
2.168 10 , 2.131 11 , 2.135 10
72
2
Ž .
Ž .
Ž
Ž .
171.8 2
2.474 7
2.653 1
2.182 10 , 2.131 10 , 2.138 10
x
Ž .
Ž .
Ž . Ž . Ž .
Ž .
174.1 5
IPh2 SnCH2-1,2,4-triazole
2.45 2
2.856 3
2.18 3 , 2.10 2 , 2.13 3
72
2
Ž .
Ž .
Ž . Ž . Ž .
Ž .
171.8 5
2.36 2
2.944 3
Ž .
2.19 3 , 2.09 3 , 2.15 3
Ž . Ž .
wÄ
Ž
.
4Ž
.
x
x
Ž .
2.53 1
Ž .
Ž .
w
73
w
74
w
75
w
76
w
77
x
x
x
x
x
2- Me2 N Ph Me3Si Me-C,N MePhSnBr 2.492 3
2.663 1
2.144 3 , 2.134 5 , 2.121 4
Ž . Ž . Ž .
2.13 1 , 2.16 1 , 2.21 1
171.3 1
w
Ž
.
Ž .
Ž .
Ž .
8- Me2 N -1-naphthyl 2-MeSnI
2.950 2
171.5 2
Ž
w
.
Ž .
C5H5N Me3SnCl
2.42 4
2.7391 7
Ž .
2.73 2
Ž
.Ž
.x
Ž .
2.654 17
Ž .
Ž .
Ž .
Ž .
Ž .
174.32 8
Ž .
177.3 4
C10 H5 OMe-5 CH2 NMe2-8 MePhSnBr 2.401 4
2.147 4 , 2.134 6 , 2.141 4
wŽ .x
.
Ž
.
Ž . Ž . Ž
.
CN Me3SnCl
2.128 12 , 2.128 14 , 2.129 15
a When there are two independent molecules, two lines of data are found.

(
)
362
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
zole plane, whereas in B the tin was almost coplanar
with the plane of the imidazole donor. The donor La
also shows different conformations in adducts A and B.
This is most evident when considering the dihedral
A, the methyl group seems to have more, and relatively
stronger, repulsive interaction with the surrounding
Ž
. Ž
atoms than in B. In fact C 6A according to the model
.
adopted for the hydrogens has 5 interactions below 3.6
A with atoms not belonging to the same imidazole
group 3.348 A with C 23A and 3.580 A with C 22A ,
for example , whereas in B there are no intermolecular
˚
Ž .
Ž . Ž . Ž .
Ž .
Ž . Ž .
angles C 7 –Sn 1 –N 1 –C 2 and C 7 –Sn 1 –N 1 –
˚
˚
Ž . Ž . Ž .
Ž
Ž
.
Ž
.
C 5 which have values of 178.7 5 8 and y6.4 6 8 for
Ž . Ž .
.
molecule A and y19.2 5 8 and 172.4 5 8 for molecule
˚
Ž .
B. In molecule A C 2 adopts a trans conformation
contacts below 3.8 A.
Ž .
with respect to C 7 , whereas the cis is preferred in
The phenyl rings seem to adopt substantially the
same conformation in adducts A and B. In fact, for the
same adduct, the dihedral angles between phenyl planes,
do not differ by more than 208, and in many cases not
more than 58.
molecule B. This different orientation of the ligand may
explain the small but not negligible difference between
the geometry of the two molecules. In particular, the
Ž . Ž . Ž .
Ž . Ž . Ž .
angles Sn 1 –N 1 –C 2 and Sn 1 –N 1 –C 5 which
Ž .
Ž .
Ž .
change from 128.6 4 and 125.7 4 8 in B to 123.5 4 8
In Table 8, selected bond distance and angles of
a
Ž .
wŽ
.
x
and 131.0 4 8 in A, with a tilting of the plane around its
L Ph3SnCl 8 are compared with the values reported
w
x
normal position of more than 58. The rotation of almost
all of the imidazole passing from A to B seems to affect
Ž . Ž .
even the bond lengths. The N 1 –C 2 bond, which has
for other R3SnXN compounds 57,60–77 . Several gen-
eral patterns emerge: all the complexes have a distorted
trigonal bipyramidal configuration with the organic
groups in the equatorial position and the more elec-
tronegative nitrogen and halide in the axial positions.
The most interesting feature is that the minimum Sn–N
distance, and hence the strong donor interaction, is
found in the derivatives showing the maximum Sn–X
distance. The relevant geometrical data match perfectly
well with the curves deduced by Britton and Dunitz
˚
˚
Ž .
Ž .
a value of 1.304 7 A in A becomes 1.324 7 A in B,
˚
Ž . Ž . Ž
Ž .
and 1.374 7 A in B . It is also interesting to note that
and the same is true for N 1 –C 5 1.359 7 A in A
˚
Ž .
.
Ž
.
the shorter bond lengths around N 1A are more similar
to the non-perturbed or weakly perturbed 1-methyl-
imidazole 59 G.W. Rabe et al., not published, 1996 ,
and that is consistent with the longer Sn 1A –N 1A
bond length observed.
Ž
.
w
x
Ž
.
.
Ž
.
Ž
w
x
51 ; the axial arrangement of N and X can be seen as a
The other major difference between molecules A and
B is in the N–CH3 fragment. The N–C bond length is
‘snapshot’ of the SN 2 pathway for substitution with
inversion at tetrahedral Sn, where the N-lone pair acts
as the incoming nucleophile and X as the leaving group.
˚
.
Ž
Ž .
remarkably shorter in adduct A 1.455 8 A with re-
˚
Ž
Ž .
spect to adduct B 1.483 7 A; the bond angles for
C 2 –N 3 –C 6 and C 4 –N 3 –C 6 are, respectively,
128.5 6 8 and 126.1 6 8 for A, whereas they are
125.0 6 8 and 127.1 5 8 for B. A probable explanation
a
Ž . Ž . Ž .
Ž . Ž . Ž .
[(
L
)
w
] (
)
x
3.6.2. Diffraction study of
2 Me2 SnBr2 10
L
a
Ž . Ž .
Ž
.
The molecular structure of
shown in Fig. 6, together with the numbering scheme.
The bond distances and angles are reported in Table 9.
2 Me2 SnBr2 10 is
Ž .
Ž .
Ž .
in this case is the different environment around C 6 . In
a
wŽ . Ž
.
x Ž
.
Fig. 6. The molecular structure of
L
CH3 2 SnBr2 10 with atom numbering, as used in the crystallographic work.
2

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
363
Table 9
Selected interatomic distance A and bond angles deg with e.s.d. in
Table 10
˚
˚
Ž .
Ž .
x
parentheses, for bis 1-methylimidazole dimethyltin IV dibromide
Ž
.
Ž
Ž
.
Selected interatomic distance A and bond angles deg with e.s.d. in
parentheses, for bis 1-methylimidazole diethyltin IV diiodide 18
w
Ž
.
Ž
.
w
Ž
.
.
x Ž .
Ž .
10
Bond lengths
Ž . Ž .
Sn 1 –N 1
Ž .
2.9904 4
Bond lengths
Sn 1 –I 1
Ž . Ž .
Ž .
Sn 1 –N 1
Ž .
Ž .
2.7384 3
Ž .
2.366 5
Sn 1 –Br 1
Ž . Ž .
Ž .
2.336 3
Ž . Ž .
Ž .
2.148 9
Sn 1 –C 7
Ž . Ž .
Ž .
2.125 3
Ž . Ž .
Ž .
1.321 7
Sn 1 –C 7
N 1 –C 2
Ž . Ž .
Ž .
1.323 4
Ž . Ž .
Ž .
1.377 8
N 1 –C 2
N 1 –C 5
Ž . Ž .
Ž .
1.370 5
Ž . Ž .
Ž .
1.354 8
N 1 –C 5
N 3 –C 2
Ž . Ž .
Ž .
1.331 4
Ž . Ž .
Ž .
1.358 8
N 3 –C 2
N 3 –C 4
Ž . Ž .
Ž .
1.358 5
Ž . Ž .
Ž .
1.473 8
N 3 –C 4
N 3 –C 6
Ž . Ž .
Ž .
1.459 4
Ž . Ž .
Ž .
1.345 9
N 3 –C 6
C 4 –C 5
Ž . Ž .
Ž .
1.347 5
Ž . Ž .
Ž .
1.42 3
C 4 –C 5
C 7 –C 8
Ž . Ž .
Ž .
1.27 3
C 7 –C 9
Bond angles
Ž . Ž .
N 1 –Sn 1 –N 1
Ž .
Br 1 –Sn 1 –Br 1
180.00
180.00
180.00
Bond angles
Ž .
Ž . Ž .
Ž .
Ž . Ž .
I 1 –Sn 1 –I 1
180.00
180.00
179.99
Ž . Ž . Ž .
Ž .
Ž . Ž .
C 7 –Sn 1 –C 7
N 1 –Sn 1 –N 1
Ž . Ž . Ž .
Ž .
Ž . Ž . Ž .
C 7 –Sn 1 –Br 1
Ž . Ž . Ž .
88.3 1
C 7 –Sn 1 –C 7
Ž .
89.5 1
Ž . Ž . Ž .
Ž .
C 7 –Sn 1 –N 1
C 7 –Sn 1 –I 1
Ž . Ž . Ž .
88.3 3
Ž .
Ž . Ž .
Ž .
Ž .
89.2 3
Br 1 –Sn 1 –N 1
Ž . Ž . Ž .
88.99 7
C 7 –Sn 1 –N 1
Ž .
Ž .
Ž . Ž .
Ž .
88.3 1
Sn 1 –N 1 –C 2
125.2 2
l 1 –Sn 1 –N 1
Ž . Ž . Ž .
Ž .
Ž . Ž . Ž .
Ž .
127.0 4
Sn 1 –N 1 –C 5
129.1 2
Sn 1 –N 1 –C 2
Ž . Ž . Ž .
Ž .
Ž . Ž . Ž .
Ž .
127.4 4
N 1 –C 2 –N 3
111.0 3
Sn 1 –N 1 –C 5
Ž . Ž . Ž .
Ž .
Ž . Ž . Ž .
Ž .
110.5 5
C 2 –N 3 –C 6
126.0 3
N 1 –C 2 –N 3
Ž . Ž . Ž .
Ž .
Ž . Ž . Ž .
Ž .
125.2 6
C 2 –N 3 –C 4
107.5 3
C 2 –N 3 –C 6
Ž . Ž . Ž .
Ž .
Ž . Ž . Ž .
Ž .
107.5 5
C 4 –N 3 –C 6
126.5 3
C 2 –N 3 –C 4
Ž . Ž . Ž .
Ž .
Ž . Ž . Ž .
Ž .
N 3 –C 4 –C 5
106.7 3
C 4 –N 3 –C 6
127.2 6
Ž .
106.6 6
Ž . Ž . Ž .
Ž .
Ž . Ž . Ž .
C 4 –C 5 –N 1
109.2 3
N 3 –C 4 –C 5
Ž . Ž . Ž .
Ž .
Ž . Ž . Ž .
Ž .
109.8 6
C 5 –N 1 –C 2
105.6 3
C 4 –C 5 –N 1
Ž . Ž . Ž .
Ž .
105.6 5
124.8 12
Ž
126.6 14
C 5 –N 1 –C 2
Ž . Ž . Ž .
Ž
.
.
Sn 1 –C 7 –C 8
Ž . Ž . Ž .
Sn 1 –C 7 –C 9
The tin atom exhibits a slightly distorted octahedral
coordination geometry with two Br atoms, two methyl
C atoms and the N atoms of two 1-methylimidazole
ligands in all-trans configuration. The Sn–C, Sn–N,
Sn–Br and ligand bond distances are identical in pairs.
The bond angles around the six-coordinated tin do not
deviate more than 1.78 from ideality and they are simi-
a
w
Ž
.
xw
x
lar to those found in
L
2 Me2 SnCl2 55 . The 1-
a
wŽ . Ž
.
x Ž
.
Fig. 7. The molecular structure of
L
C2 H5 2 SnI2 18 with atom numbering, as used in the crystallographic work.
2

Table 11
Values of the angles 8 and bond lengths A concerning 1-methylimidazole derivatives
a
˚
Ž .
Ž .
N1–C2–N3
Ž .
Compound
C2–N3–C4
Ž .
N3–C4–C5
Ž .
C4–C5–N1
Ž .
C5–N1–C2
Ž .
N1–C2
C2–N3
N3–C4
C4–C5
C5–N1
Ref.
a
wŽ
wŽ
wŽ
.
.
.
x
Ž .
Ž .
Ž .
Ž .
Ž .
L
2 Me2 SnBr2
2 Et2 Snl2
Ph3SnCl
111.0 3
107.5 3
106.7 3
109.2 3
105.6 3
1.323 4
Ž .
1.331 4
Ž .
1.358 5
Ž .
1.347 5
Ž .
1.370 5
Ž .
1.377 8
this work
this work
this work
a
x
Ž .
Ž .
Ž .
Ž .
Ž .
L
110.5 5
107.5 5
106.6 6
109.8 6
105.6 5
1.321 7
1.354 8
1.358 8
1.345 9
a
x
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
L
112.4 5
105.4 5
107.7 5
109.1 6
105.4 5
1.304 7
1.328 7
1.360 8
1.329 8
1.359 7
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
111.1 5
107.8 5
Ž .
106.0 5
Ž .
110.1 5
Ž .
105.0 5
Ž .
1.324 7
1.328 7
1.364 8
1.339 8
1.374 7
a
wŽ
.
x
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
w
w
w
x
55
x
59
x
81
L
2 Me2 SnCl2
111.0 2
107.2 2
106.8 2
109.1 2
105.9 2
1.322 3
Ž .
1.338 2
Ž .
1.362 3
Ž .
1.349 3
Ž .
1.371 2
Ž .
1.363 3
La
112.2 3
106.6 3
106.2 3
110.1 3
104.9 3
1.288 3
1.338 3
1.347 3
1.335 3
Ž .
Ž .
Ž .
Ž .
Ž .
a
b
w
Ž
.Ž . x
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
trans- Fe bpc L
ClO4
111.8 4
106.8 4
106.8 4
109.7 4
104.8 4
1.323 6
1.331 6
1.364 6
1.341 7
1.373 5
Ž .
1.390 5
2
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
111.5 4
107.2 4
Ž .
106.9 4
Ž .
108.7 4
Ž .
105.7 4
Ž .
1.318 6
1.338 6
1.370 6
1.350 7
a
Ž
L
.
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
w
x
82
trans-Cl2
2Cu
110.6 4
107.6 4
106.6 4
108.8 4
106.4 4
1.325 6
Ž .
1.351 7
Ž .
1.382 6
Ž .
1.356 8
Ž .
1.395 6
Ž .
1.392 8
Ž .
Ž .
Ž .
Ž .
Ž .
109.7 4
Ž .
108.4 5
107.0 6
107.9 5
107.1 5
1.333 6
1.345 7
1.371 7
1.363 9
a
Ž
.
Ž
.
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
w
83
w
84
w
85
w
86
w
87
w
88
x
x
x
x
x
x
cis- CO 2Cl L Rh
112.1 5
107.5 5
y
105.9 6
y
111.1 6
y
103.5 5
y
1.327 7
1.338 7
1.357 8
1.343 9
1.381 9
Ž .
1.377 6
a
d
Ž
.
Ž .
Ž .
Ž .
Ž .
L
-Porph-Zn
y
1.307 6
1.345 6
1.372 7
1.336 8
a
Ž
L
.
Ž .
Ž .
Ž .
Ž .
Ž .
Ž
.
Ž
.
Ž
.
Ž
.
Ž
.
cis-Cl2
2 Pt
110.5 7
107.0 7
106.7 7
108.9 7
107.0 6
1.301 10
1.345 10
1.370 10
1.338 11
1.369 10
a
)
e
Ž
Ž
Ž
.
.
.
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
L
-Porph -Co
-Porph -Mn
111.5 4
106.5 4
106.5 4
110.0 4
105.6 3
1.316 6
1.365 6
1.371 6
1.355 7
1.377 5
Ž .
1.378 4
a
)
e
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
L
111.8 3
y
107.1 2
y
107.0 2
y
109.7 3
y
104.4 2
y
1.295 4
1.348 4
1.326 4
1.338 5
a
Ž
. Ž
.
Ž
.
.
.
.
.
.
Ž
.
.
.
.
.
.
L
6 Fe BPh4 CH2Cl2
1.270 23
y
y
y
y
y
y
y
y
y
y
y
y
1.382 25
2
Ž
Ž
1.426 24
y
y
y
y
y
1.320 24
y
y
y
y
y
Ž
Ž
1.325 24
y
y
y
y
y
1.325 26
Ž
Ž
1.367 26
y
y
y
y
y
1.309 23
Ž
Ž
1.397 23
y
y
y
y
y
1.347 26
Ž
Ž
y
y
y
y
y
1.308 30
1.407 28
a
Ž
Ž
.
.
Ž
.
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
w
x
89
L
6Cd NO3
111.3 4
107.8 4
105.2 4
110.5 4
105.2 4
1.312 5
1.327 6
1.347 7
1.355 7
Ž .
1.343 6
2
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
111.1 4
107.1 5
106.6 6
109.1 5
106.1 4
1.337 7
Ž .
1.329 7
1.379 8
1.359 9
1.363 7
Ž .
1.365 7
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
110.5 4
y
108.2 4
y
105.6 5
y
110.1 5
y
105.6 5
y
1.306 7
1.345 7
y
1.345 8
y
1.346 8
y
a
Ä
Ž
. 4
Ž .
Ž .
w
90
w
91
w
92
x
x
x
L
4Cu ONC CN
1.314 3
1.375 2
2
2
Ž .
Ž .
y
y
y
y
y
1.314 2
y
y
y
1.367 2
a
c
wŽ
wŽ
.
Ž .x
Co Q
Ž .
Ž .
105.4 9
Ž .
108.2 9
Ž .
109.2 9
Ž .
Ž .
Ž .
Ž .
Ž .
L
112.0 9
105.3 8
1.30 1
Ž .
1.35 2
1.34 1
y
1.36 1
Ž .
1.38 1
Ž .
110.0 1
Ž .
110.0 1
Ž .
104.0 1
Ž .
111.0 1
Ž .
Ž .
Ž .
104.4 9
1.34 1
1.31 2
1.36 1
y
a
.
x
Ž .
Ž .
Ž .
Ž .
1.354 9
Ž .
Ž .
Ž .
Ž .
1.365 9
L
6 Ni S8
103.8 5
1.327 8
1.324 9
1.362 9
Ž .
Ž .
Ž .
Ž .
Ž .
105.3 5
1.324 8
Ž .
1.343 8
1.363 9
1.345 9
1.34 1
1.364 8
Ž .
1.383 8
Ž .
Ž .
Ž .
105.2 5
1.329 8
1.360 9
1.363 9

Compound
N1–C2–N3
Ž .
110.9 4
C2–N3–C4
Ž .
107.1 4
N3–C4–C5
Ž .
107.6 4
C4–C5–N1
Ž .
107.8 4
C5–N1–C2
Ž .
106.5 4
N1–C2
Ž .
1.316 6
C2–N3
Ž .
1.336 6
N3–C4
Ž .
1.360 7
C4–C5
Ž .
1.349 7
C5–N1
Ž .
1.383 6
Ref.
a
wŽ
L
.
x
w
w
w
w
x
93
x
94
x
95
x
96
4 F2 Fe BF4
110.8 4
107.5 4
106.9 4
108.6 4
106.2 3
1.319 6
1.348 6
1.370 6
1.351 7
1.394 6
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
a
w
L
.
Ž
. x
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
4Co NCS
111.7 3
106.7 2
106.6 3
109.4 3
105.5 2
1.318 4
Ž .
1.349 4
Ž .
1.370 4
Ž .
1.358 4
Ž .
1.378 4
Ž .
2
Ž .
Ž .
Ž .
Ž .
Ž .
111.1 3
108.1 3
106.1 3
109.4 3
105.3 3
1.321 4
1.333 4
1.337 4
1.366 4
1.359 4
a
wŽ
wŽ
.
.
Ž
.
x
Ž .
Ž .
Ž .
Ž .
Ž .
105.6 7
Ž
.
.
Ž
.
.
.
.
.
Ž
.
.
.
.
.
Ž
.
.
.
.
.
.
Ž
.
.
.
.
.
L
2 Re PPh3 Cl3
111.5 7
107.8 7
106.1 7
108.9 7
1.328 10
1.335 10
1.377 13
1.368 12
1.391 10
Ž .
Ž .
Ž .
Ž .
Ž .
Ž
Ž
Ž
Ž
Ž
110.6 7
Ž .
108.3 7
Ž .
108.3 13
105.7 7
Ž .
112.7 14
109.4 8
Ž .
104.4 10
106.0 7
1.331 11
1.336 10
1.351 12
1.375 13
1.355 11
a
xq
Ž .
Ž .
Ž
Ž
Ž
Ž
L
4ReO2
109.9 7
108.1 7
105.8 7
109.4 7
106.8 7
1.330 9
1.344 12
1.370 11
1.366 13
1.359 11
Ž .
Ž
.
Ž
.
.
Ž
.
.
Ž .
Ž
.
.
Ž
Ž
Ž
Ž
108.5 9
105.7 8
1.329 12
1.369 13
1.381 21
1.378 16
1.367 12
Ž .
Ž .
Ž
Ž
Ž .
Ž
Ž
Ž
Ž
Ž
112.7 8
Ž .
107.3 9
105.1 11
111.2 11
103.7 8
Ž .
1.289 11
1.326 12
1.313 16
1.352 17
1.333 14
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž
Ž .
110.1 5
108.4 5
106.0 6
109.4 0
106.0 6
1.329 8
1.342 7
1.345 9
1.368 10
1.357 9
a
wŽ
.
.
.
Ž
.x
Ž .
111.7 4
Ž .
Ž .
Ž .
Ž .
104.7 4
Ž .
Ž .
Ž .
Ž .
Ž .
w
w
x
x
L
4ReO OCH3
106.9 4
107.3 4
109.4 4
1.319 5
1.326 5
1.359 6
1.325 7
1.381 5
97
Ž
PF6
2
a
wŽ
Ž
Ä
Ž .
Ž .
110.5 5
Ž .
107.3 5
Ž .
108.2 5
Ž .
107.7 5
Ž .
106.4 5
Ž .
1.333 7
Ž .
1.326 6
Ž .
1.364 7
Ž .
1.339 7
Ž .
1.385 6
L
4ReO OP O
97
.42q
OCH3
Ž .
110.2 5
Ž .
107.4 5
Ž .
107.3 5
Ž .
108.4 5
Ž .
106.7 4
Ž .
1.320 6
Ž .
1.330 6
Ž .
1.373 7
Ž .
1.331 7
Ž .
1.378 6
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
1.386 7
109.9 6
108.9 5
106.9 6
108.0 6
106.3 5
1.326 7
1.324 7
1.351 8
1.349 8
Ž .
111.1 10
Ž .
106.9 10
Ž .
107.7 10
Ž .
107.3 11
Ž .
Ž .
Ž .
Ž .
Ž .
Ž .
1.387 6
109.6 5
108.4 5
107.3 5
107.9 5
106.9 4
1.336 7
1.326 6
1.370 8
1.343 8
a
wŽ
L
.
Ž
.xŽ
.
Ž
.
.
Ž
.
Ž
.
.
.
Ž
.
.
.
.
Ž .
Ž
.
.
.
.
Ž
.
.
.
.
Ž .
Ž .
1.37 2
Ž
.
.
.
.
w
x
97
4ReO OBF3 I3
107.0 9
1.300 12
1.347 12
1.33 2
1.364 12
Ž
Ž .
Ž
Ž
Ž .
Ž
Ž
Ž
.
.
.
Ž
.
.
.
Ž
111.1 10
107.3 9
107.2 11
109.1 10
105.3 9
1.307 12
1.324 12
1.349 14
1.322 13
1.375 12
Ž .
Ž .
Ž
Ž
Ž .
Ž
Ž
Ž
Ž
Ž
109.0 9
107.9 8
107.1 10
108.6 11
107.4 8
1.315 12
1.338 11
1.350 14
1.331 14
1.357 12
Ž .
Ž .
Ž .
Ž
Ž .
Ž
Ž
Ž
Ž
Ž
109.9 9
107.3 8
108.5 9
109.6 10
104.6 8
1.333 11
1.333 11
1.325 13
1.301 12
1.366 12
Minimum
Maximum
Average
Number of entries
108.5
112.7
110.9
38
105.4
110.0
107.5
38
104.0
112.7
106.8
38
104.4
111.2
109.1
38
103.5
107.4
105.6
40
1.270
1.347
1.32
50
1.31
1.369
1.34
42
1.313
1.382
1.36
42
1.301
1.378
1.35
40
1.325
1.426
1.38
50
a When there are two independent molecules or two or more different imidazoles, two or more lines of data are found.
b
Ž
.
.
H2bpcs4,5-dichloro-1,2-bis 2-pyridinecarboxamido benzene .
c
X
Ž
.
H2Qs N,N -bis 5-mercapto-3-methyl-1-phenylpyrazol-4-ylmethylene -ortho-phenylenediamine.
d Porphs2,3,7,8,12,13,17,18-octaethylporphinato.
e Porph) sa,b,d,l-tetraphenyl-porphinato.

(
)
366
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
˚
Ž .
.
methylimidazole ligands are bonded to the metal through
their pyridine-like nitrogen atom.
1.27 3 A compared with the expected values for this
kind of bond.
The Sn–N distance compares well with those of
The 1-methylimidazole ligands are bonded to the
metal through their pyridine-like nitrogen atom. The
azole rings are planar, with no atom deviating from the
least-squares plane through the five atoms by more than
similar all-trans complexes, having an sp2 nitrogen
˚
containing ligands, which span between 2.311 A and
˚
˚
Ž
2.393 A with a mean value of 2.359 A 16 entries on
CCDC data base 78 . The Sn–N distance in our
determination is slightly longer with respect to
Me2 SnCl2 L 2 , the same kind of behaviour being
˚
.
w x
0.001 A. The N–CH bond is also very close to the ring
3w
Ž
.
xw x
2 M e 2 SnC l 2 55
a
plane. U nlike
L
and
a
a
Ž
.
w
Ž
.
x
Ž
L
2 Me2 SnBr2 10 where the Sn atom deviates out
of the imidazole plane by 0.1473 3 A and 0.1239 8 A,
respectively the tin atom in
coplanar with the imidazole plane. The Sn–I bond
distance 2.9904 4 A compares well with the value
w Ž .
found in the bis 8- dimethylamino -1-
naphthyl methyltin IV iodide, for which a hexacoordi-
nate octahedral configuration has been attributed by the
˚
˚
Ž .
Ž
.
Ž
. w x
XsCl, Br 79,80 .
Ž .
found for Me2 SnX2 pyrazole
2
a
.
w
Ž
. x
L 2 Et2 SnI2 is almost
The azole rings are planar, with no atom deviating from
the least-squares plane through the five atoms by more
˚
˚
.
Ž
Ž .
than 0.004 A. The N–CH3 bond is also very close to
˚
.
A
Ž
Ž .
2.950 2
the ring plane. On the other hand, the tin atom deviates
˚
Ž .
x
Ž
.
by 0.1239 8 A out of the imidazole plane. It is interest-
ing to note that in our study the N–CH3 bond is shorter
a
˚
w
Ž
.
x w x
w
x
than in
L
2 Me2 SnCl2 55 by 0.024 A. The angle
authors 74 , and also with the few other cases of trans
diiodo six-coordinate tin values of 3.016 A, and 2.965
˚
Ž
between the imidazole ring and the Sn–Br–N plane is
30.08 1 greater than the values found for the chloro
analogue 268 and in the range of values found for 16
independent all-trans SnR2 X2 N2 adducts 5–468 .
The bond distances and bond angles of La found in
this complex are very similar to those observed in other
˚
˚
Ž .
w
x
A, and 3.009 A are reported by Tursina et al. 102 and
Jastrzebski et al. 103 respectively, for similar trans
Ž
.
w
x
Ž
.
.
w
x
SnI2Y4 compounds . As already pointed out 104 for
dichloro diorganotin adducts, considerable evidence ex-
ists for the Sn-halogen bond length differences between
the trans and cis arrangements, the latter having shorter
distances with typical values for SnI2Y4 in the 2.7–2.8
w
x
1-methylimidazole complexes 55,59,81–97 . The Sn–
Br bond length is similar to that in other Me2 SnBr2 N-
Ž
˚
˚
.
.
w
x
w
x
Ž
donor 80,98,99 and longer than that observed in the
Me2 SnBr2 2,2 -azopyridine 100 , in which the N-donor
is a chelating ligand. The Sn–N distance is similar to
A range 105–108 . The Sn–N bond 2.366 A is
2
X
a
Ž
.
w
x
wŽ
.
L
xw x
2 Me2 SnCl2 55
slightly longer than that found in
a
w
Ž
. x
L 2 Me2 SnBr2 10, in agreement with the lower
and
a
w
Ž
.
xw x
those in
L
2 Me2 SnCl2 55 , but slightly shorter than
Lewis acidity of diiodo with respect to dichloro and
a
w
Ž
.
x
Ž . Ž . Ž .
that in L Ph3SnCl 8. The Sn 1 –N 1 –C 5 angle is
dibromo diorganotin compounds, but shorter than both
a
Ž . Ž . Ž .
w
Ž
.
x
greater than the Sn 1 –N 1 –C 2 one. These angles are
in the two molecules of L Ph3SnCl 8, in agreement
of the same order of magnitude as those in
with the lower Lewis acidity of triorgano compared to
a
w
Ž
Ž
.
xw
x
Ž
.
L
2 Me2 SnCl2 55 and in molecule
A
of
diorganotin IV derivatives.
a
a
w
.
x
wŽ
. x
L 2 Et2 SnI2 18
L Ph3SnCl 8, whereas they have an opposite trend
A significant difference between
and the other structurally characterized diorganotin IV
Ž
.
with respect to those observed in molecule B.
derivatives, containing 1-methylimidazole ligands, is in
the relative magnitudes of the Sn 1 –N 1 –C 5 and
a
[(
L
)
] (
)
Ž . Ž . Ž .
3.6.3. Diffraction study of
2 Et2aSnI2 18
wŽ
. x
L 2 Et2 SnI2 18 is
Ž . Ž . Ž .
127.0 4 8 and 127.4 4 8, respectively . Bond distance
and angles for 1-methylimidazole are substantially simi-
lar to the values found in
the N–CH3 bond distance, which is longer in 18 than in
10 and closer to the value reported for L 2 Me2 SnCl2 .
The molecular structure of
Sn 1 –N 1 –C 2 angles which are similar only in 18
Ž
Ž .
Ž .
.
shown in Fig. 7, together with the numbering scheme.
The bond distances and angles are reported in Table 10.
The tin atom is octahedrally coordinated to two I
atoms, two ethyl groups and the N atoms of two
1-methylimidazole ligands in an all-trans configuration.
The adduct shows a Ci internal symmetry, with the Sn
on a crystallographic center of symmetry, bond angles
and distances are then equal in pairs. The ethyl groups
in this structure seem to have the CH3 group disordered
over two different sites with almost equal occupation
a
w
Ž
. x
L 2 Me2 SnBr2 except for
a
w
Ž
.
x
The angle between the imidazole ring and the Sn–I–N
Ž
.
occupation 0.504 and 0.496 . This occurrence is not
w
x
new in compounds of this kind 101 and is probably
due to a large thermal motion the crystal seems to
Ž
.
decay for a f20% during data collection and to the
peripheric position of the disordered carbon. It is there-
fore impossible to make any precise statement on the
geometry of the ethyl group. The C–C distance is in
Fig. 8. Atom numbering scheme of the imidazole ring used through-
out this paper.
˚
Ž
Ž .
fact alternatively too long or too short 1.61 4 A and

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
367
plane is 23.58, remarkably lower than in
Acknowledgements
a
w
Ž
.
x
2 M e 2 SnB r2
L
and m ore sim ilar to
a
w
Ž
.
x
L 2 Me2 SnCl2 .
Examination of the imidazole moiety Fig. 8 in the
We thank the MURST, CNR-Rome and the Universi-
ties of Camerino and Palermo for financial help.
Ž
.
a
w
Ž
.
x
m olecular structures of
L
M e 2 SnCl 2
,
x
2 w
Ž
.
a
a
a
w
Ž
.
x w
2 Me2 SnBr2 ,
Ž
.
x
L
L
2 Et2 SnI2 and L Ph3SnCl
allows some empirical rules to be made. Some of them
are probably valid for all the 1-methylimidazole deriva-
References
w
x
Ž
.
tives 55,59,91–94 , some only for organotin IV com-
plexes. Several general patterns emerge which had not
been noted previously; this may be due to the fact that
the first structural data reported for imidazole those
concerning non-coordinated imidazoles 109–113 and
some of their zinc II derivatives 114,115 , and dis-
cussed in literature, were peculiar and that often struc-
tures were not published but only selected data; some-
times, no data, not even atomic coordinates are avail-
able.
w x
1
C. Pettinari, F. Marchetti, M. Pellei, A. Cingolani, L. Barba,
A. Cassetta, J. Organomet. Chem. 515 1996 119.
Ž
.
w x
Ž
. Ž
.
2
w x
3
A.J. Crowe, P.J. Smith, Chem. Ind. London 1980 200.
A.J. Crowe, P.J. Smith, G. Atassi, Chem. Biol. Interact. 32
Ž
x
Ž
.
1980 171.
w
w x
4
A.G. Davies, P.J. Smith, Comprehensive Organometallic
Ž .
w
x.
Ž
.
Chemistry, G. Wilkinson Ed. , Pergamon, Oxford, 1982, pp.
519–627.
w x
5
C. Pettinari, F. Marchetti, A. Cingolani, S. Bartolini, Polyhe-
Ž
.
dron 15 1996 1263.
w x
6
A.C.T. North, D.C. Phillips, F.S. Mathews, Acta Crystallogr.
Ž
.
A24 1968 351.
In all the 1-methylimidazole derivatives listed in
Table 11 it is found that:
w x
7
A. Altomare, G. Cascarano, C. Giacovazzo, A. Guagliardi, J.
Ž
.
Appl. Cryst. 26 1993 343.
Ž . Ž . Ž .
w x
8
1. N 1 –C 2 –N 3 is never the smallest internal angle;
D.J. Watkin, J.R. Carruthers, P.W. Bettridge, CRYSTALS
User Guide, Chemical Crystallography Laboratory, University
of Oxford, Oxford.
rather, it is often the widest.
Ž . Ž . Ž .
2. C 4 –N 3 –C 2 is always the smallest internal an-
w x
Ž .
9
D.J. Watkin, Acta Crystallogr. A50 1994 411.
gle.
w
x
10 E. Prince, P.T. Boggs, International Tables for Crystallogra-
Ž . Ž . Ž .
Ž . Ž .
3. C 5 –C 4 –N 3 is always larger than N 1 –C 5 –
Ž
.
phy, A.J.C. Wilson Ed. , Vol. C, Kluwer Academic Publish-
ers, Dordrecht, 1992.
Ž . Ž . Ž . Ž .
C 4 and C 2 –N 1 –C 5 .
w
w
x
Ž
.
11 J.R. Carruthers, D.J. Watkin, Acta Crystallogr. A35 1979
698.
Ž . Ž . Ž .
4. C 2 –N 1 –C 5 is not significantly different from
Ž . Ž . Ž .
N 1 –C 5 –C 4 .
x
Ž
.
12 A.J.C. Wilson Ed. , International Tables for Crystallography,
Vol. C, Kluwer Academic Publishers, Dordrecht, 1992.
Ž . Ž .
5. N 3 –C 2 is often the shortest bond length.
Ž . Ž .
6. N 3 –C 4 is the longest bond length.
w
w
w
w
x
Ž
.
13 M. Nardelli, Comput. Chem. 7 1983 95.
Ž . Ž .
Ž . Ž .
x
Ž
.
7. N 1 –C 5 is generally longer than C 2 –N 1 and
14 G.M. Sheldrick, Acta Crystallogr. A46 1990 467.
x
Ž
.
15 K.A. Kocheshkov, Chem. Ber. 62 1926 996.
Ž . Ž .
C 4 –C 5 .
x
16 R.J. Watts, J.S. Harrington, J. Van Houten, J. Am. Chem. Soc.
Ž . Ž .
Ž . Ž .
8. C 4 –C 5 and C 2 –N 1 are not significantly dif-
ferent.
Ž
.
99 1977 2179.
w
x
17 G.W. Bushnell, K.R. Dixon, M.A. Khan, Can. J. Chem. 52
No pattern is evident for the external bond angle
Ž
.
1974 1367.
Ž . Ž .
C 1 –N 1 –C 5 .
Ž . Ž .
Ž . Ž . Ž .
w
w
x
x
Ž
.
M–N 3 –C 2 , M–N 3 –C 4 , C 1 –N 1 –C 2 and
18 K.R. Dixon, Inorg. Chem. 16 1977 2618.
19 N.W. Alcock, J.F. Sawyer, J. Chem. Soc. Dalton Trans. 1977
Ž
.
Ž . Ž . Ž .
1090.
Although the eight generalizations seem to be sup-
ported by abundant evidence, we do not state that
structural parameters which do not fit into the patterns
defined above are impossible. They will probably be
found for imidazole derivatives characterized by some
singular or remarkable property. To date, we have
observed only few exceptions which are or associated
with either steric hindrance or strong metal–azole inter-
w
w
w
x
Ž
Ž
.
.
20 N. Ohkaku, K. Nakamoto, Inorg. Chem. 12 1993 2440.
x
21 I.R. Beattie, G.P. McQuillan, J. Chem. Soc. 1963 1519.
x
22 G. Nieuwpoort, J.G. Vos, W.L. Groeneveld, Inorg. Chim. Acta
Ž
.
29 1978 117.
w
w
x
23 R.C. Poller, The Chemistry of Organotin Compounds, Logos,
London, 1970.
x
24 W.P. Newman, The Organic Chemistry of Tin, Wiley, New
York, 1970.
w
w
x
Ž
.
25 B.W.K. Ho, J.J. Zuckerman, Inorg. Chem. 12 1973 1552.
w
x
x
actions 116–120 .
26 F. Huber, M. Vornefeld, G. Ruisi, R. Barbieri, Appl.
Ž
.
Organomet. Chem. 7 1993 243.
w
w
x
Ž
.
27 W.F. Edgell, C.H. Ward, J. Mol. Spectrosc. 8 1962 343.
x
28 J.K. Sandhu, G. Kaur, J. Holecek, A. Licka, J. Organomet.
Ž
.
Chem. 345 1988 51.
4. Supplementary material available
w
x
29 R.J.H. Clark, A.G. Davies, R.J. Puddephatt, J. Chem. Soc. A
Ž
.
1968 1828.
w
w
x
x
Ž
.
30 A.L. Smith, Spectrochim. Acta 24A 1968 695.
31 J.R. Durig, R. Layton, D.W. Sink, B.R. Mitchell, Spectrochim.
Tables of atomic coordinates, isotropic equivalent
thermal parameters, tables of structures factors, full list
of bond lengths and angles, tables of isotropic displace-
ment parameters, and dihedral angles between least-
square planes are available from one of the authors.
Ž
.
Acta 21 1965 1367.
w
w
x
x
Ž
.
32 R.J. Inskeep, J. Inorg. Nucl. Chem. 24 1962 763.
33 L.E. Moore, R.B. Gayhart, W.E. Bull, J. Inorg. Nucl. Chem.
Ž
.
26 1964 896.

(
)
368
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
w
x
Ž
.
34 A.B.P. Lever, E. Mantovani, B.S. Ramaswamy, Can. J. Chem.
K. Goubitz, D. Heijdenrijk, J. Organomet. Chem. 409 1991
157.
Ž
.
49 1971 1957.
w
w
x
x
Ž
.
w
w
w
w
w
x
35 F.A. Cotton, D.M.L. Goodgame, J. Chem. Soc. 1960 5267.
36 R.J. Restivo, A. Costin, G. Ferguson, A.J. Carty, Can. J.
70 J. Vicente, M.T. Chicote, M.C. Ramirez-de-Arellano, P.G.
Ž
.
Jones, J. Organomet. Chem. 394 1990 77.
Ž
.
x
Chem. 53 1975 1949.
71 K.M. Lo, S. Selvaratnan, S.W. Ng, C. Wei, V.G. Kumar Das,
w
x
Ž
.
37 W.A. Anderson, A.J. Carty, G.J. Palenik, G. Schreiber, Can. J.
J. Organomet. Chem. 430 1992 149.
Ž
.
x
Chem. 49 1971 761.
72 P.J. Cox, S.M.S.V. Doidge-Harrison, R.A. Howie, J.L. Wardell,
w
w
w
w
x
Ž
.
Ž . Ž
.
38 I. Nakagawa, J.L. Walter, J. Chem. Phys. 51 1969 1389.
39 P.C.H. Mitchell, R.J.P. Williams, J. Chem. Soc. 1960 1912.
40 A. Turco, C. Pecile, Nature 191 1961 66.
41 J. Lewis, R.S. Nyholm, P.W. Smith, J. Chem. Soc. 1961
J. Chem. Research S 1994 163.
x
Ž
.
x
73 J.T.B.H. Jastrzebski, G. van Koten, C.T. Knaap, A.M.M.
x
Ž
.
Ž
.
Schreurs, J. Kroon, A.L. Spek, Organometallics 5 1986 1551.
x
Ž
.
x
74 J.T.B.H. Jastrzebski, P.A. van der Schaaf, J. Boersma, G. van
4590.
Koten, D.J.A. de Ridder, D. Heijdenrijk, Organometallics 11
w
w
x
Ž
.
Ž
Ž
.
42 A. Sabatini, I. Bertini, Inorg. Chem. 4 1965 959.
1992 1521.
x
.
w
w
x
x
Ž
.
43 P.A. Flinn, in: K.G. Shenoy, F.E. Wagner Eds. , Mossbauer
75 R. Hulme, J. Chem. Soc. 1963 1524.
¨
Isomer Shift, Chap. 9a, North-Holland, Amsterdam, 1978, p.
76 G. van Koten, J.T.B.H. Jastrzebski, J.G. Noltes, G.J. Ver-
593.
hoeckx, A.L. Spek, J. Kroon, J. Chem. Soc., Dalton Trans.
w
x
Ž
.
Ž
.
44 R.V. Parish, in: G.J. Long Ed. , Mossbauer Spectroscopy
¨
1980 1352.
w
w
x
x
Ž
.
Applied to Inorganic Chemistry, Vol. 1, Plenum, New York,
1984, pp. 528 and 544.
77 S.E. Johnson, C.B. Knobler, Organometallics 11 1992 3684.
78 F. Allen, O. Kennard, D.G. Watson, L. Brammer, A.G. Orpen,
w
w
x
Ž
.
45 G.M. Bancroft, R.M. Platt, Adv. Inorg. Chem. Radiochem. 15
R. Taylor, J. Chem. Soc., Perkin Trans. 2 1987 S1.
Ž
.
w
w
w
w
w
w
w
x
1972 59.
79 G. Valle, R. Ettorre, V. Peruzzo, G. Plazzogna, J. Organomet.
x
Ž
.
Ž
.
46 B. Wrackmeyer, Ann. Rep. NMR Spectrosc. 16 1985 73.
w
Chem. 326 1987 169.
x
x
47 R.K. Harris, A. Sebald, D. Furlani, G. Tagliarini,
80 B. Alberte, A. Sanchez Gonzales, E. Garcıa, J.S. Casas, J.
`
`
`
Ž
.
Ž
.
Organometallics 7 1988 388.
Sordo, J. Organomet. Chem. 338 1988 187.
w
x
x
48 P.G. Harrison, Investigating tin using spectroscopy, in: P.G.
81 C.M. Che, W.H. Leung, C.K. Li, H.Y. Cheng, S.M. Peng,
Ž
.
Ž
.
Harrison Ed. , Chemistry of Tin, Chap. 3, Chapman & Hall,
London, 1989, pp. 61–115.
Inorg. Chim. Acta 196 1992 43.
x
82 J.A.C. van Ooijen, J. Reedijk, A.L. Spek, J. Chem. Soc.,
w
x
Ž
.
49 W.D. Honnick, M.C. Hughes, C.D. Schaeffer Jr., J.J. Zucker-
Dalton Trans. 1979 1183.
Ž
.
x
man, Inorg. Chem. 15 1976 1391, and references cited
therein.
83 F. Bonati, L.A. Oro, M.T. Pinillos, C. Tejel, M.C. Apreda, C.
Ž
.
Foces-Foces, F.H. Cano, J. Organomet. Chem. 369 1989 253.
w
w
w
x
Ž
.
x
Ž
.
50 T.P. Lockart, W.F. Manders, Inorg. Chem. 25 1986 892.
51 D. Britton, J.D. Dunitz, J. Am. Chem. Soc. 103 1981 2971.
52 J.E. Huheey, Inorganic Chemistry Principles of Structure and
84 T.D. Brennan, W.R. Scheidt, Acta Crystallogr. C44 1988
x
Ž
.
478.
x
x
85 B.J. Graves, D.J. Hodgson, C.G. van Kralingen, J. Reedijk,
Ž
.
Reactivity, 2nd edn, Chap. 6, Harper & Row, New York, 1978.
Inorg. Chem. 17 1978 3007.
w
x
w
w
x
x
Ž
.
53 E. Garcıa Martınes, A. Sanchez Gonzales, A. Macıas, M.V.
86 W.R. Scheidt, J. Am. Chem. Soc. 1974 90.
`
`
`
`
`
Ž
.
Castano, J.S. Casas, J. Sordo, J. Organomet. Chem. 385 1990
329.
87 J.F. Kirner, C.A. Reed, W.R. Scheidt, J. Am. Chem. Soc.
Ž
.
1977 2557.
w
w
x
w
w
w
w
w
w
w
x
54 U. Casellato, R. Graziani, A. Sanchez Gonzales, Acta Crystal-
88 L.L. Miller, R.A. Jacobson, Y.S. Chen, D.M. Kurtz Jr, Acta
`
`
Ž
.
Ž
.
logr. C48 1992 2125.
Crystallogr. C45 1989 527.
x
x
55 R. Bardi, A. Piazzesi, R. Ettorre, G. Plazzogna, J. Organomet.
89 P.F. Rodesiler, N.G. Charles, E.A.H. Griffith, K. Lewinski,
Ž
.
Ž
.
Chem. 270 1984 171.
E.L. Amma, Acta Crystallogr. C42 1986 396.
w
w
x
x
Ž
.
x
56 C. Pelizzi, G. Pelizzi, J. Chem. Soc., Dalton Trans. 1983 847.
57 C. Carini, C. Pelizzi, G. Pelizzi, G. Predieri, P. Tarasconi, F.
90 M. Hvastijova, J. Kozısek, J. Kohout, J. Mrozinski, L. Jager, I.
`
`
¨
Ž
.
Svoboda, Polyhedron 16 1997 463.
Ž
.
x
Vitali, J. Chem. Soc., Chem. Commun. 1990 613.
91 A.L. Nivorozhkin, H. Toftlund, M. Nielsen, J. Chem. Soc.,
w
x
Ž
.
58 P.G. Harrison, K. Molloy, R.C. Phillips, P.J. Smith, A.J.
Dalton Trans. 1994 361.
Ž
.
x
Crowe, J. Organomet. Chem. 160 1978 421.
92 S. Dev, E. Ramli, T.B. Rauchfuss, S.R. Wilson, Inorg. Chem.
w
w
x
x
Ž
.
Ž
.
59 A. Wang, B.M. Craven, J. Pharm. Sci. 68 1979 361.
60 G. van Koten, J.G. Noltes, A.L. Spek, J. Organomet. Chem.
30 1991 2514.
x
93 S. Christie, S. Subramanian, L. Wang, M.J. Zaworotko, Inorg.
Ž
.
Ž
.
118 1976 183.
Chem. 32 1993 5415.
w
w
w
w
x
x
61 J.T.B.H. Jastrzebski, J. Boersma, G. van Koten, J. Organomet.
94 A. Maslejova, S. Uhrinova, J. Mrozinski, B. Zurowska, M.C.
Ž
.
Ž
.
Chem. 413 1991 43.
Munoz, M. Julve, Inorg. Chim. Acta 255 1997 343.
x
w
w
w
w
x
Ž
.
62 K. Jurkschat, A. Tzschach, J. Meunier-Piret, M. van Meerss-
95 C. Pearson, A.L. Beauchamp, Can. J. Chem. 75 1997 220.
Ž
.
x
Ž
.
che, J. Organomet. Chem. 290 1985 285.
96 S. Belanger, A.L. Beauchamp, Inorg. Chem. 35 1996 7836.
´
´
x
x
Ž
.
63 J.T.B.H. Jastrzebski, J. Boersma, P.M. Esch, G. van Koten,
97 S. Belanger, A.L. Beauchamp, Inorg. Chem. 1996 submitted.
98 L.A. Aslanov, V.M. Ionov, V.M. Attiya, A.B. Permin, V.S.
Ž
.
x
Organometallics 10 1991 930.
x
Ž
.
64 G. van Koten, J.T.B.H. Jastrzebski, J.G. Noltes, W.M.G.F.
Petrosyan, Zh. Strukt. Khim. 19 1978 185.
Ž
.
w
x
Pontenagel, J. Kroon, A.L. Spek, J. Am. Chem. Soc. 1978
5021.
99 E. Rivarola, M. Camalli, F. Caruso, Inorg. Chim. Acta 126
Ž
.
1987 1.
w
w
w
w
w
x
w
w
w
w
x
65 U. Kolb, M. Drager, M. Dargatz, K. Jurkschat, Organometallics
100 M. Camalli, F. Caruso, G. Mattogno, E. Rivarola, Inorg. Chim.
¨
Ž
.
Ž
.
14 1995 2827.
Acta 170 1990 225.
x
x
66 M. Austin, K. Gebreyes, H.G. Kuivila, K. Swami, J.A. Zubi-
101 V. Peruzzo, G. Plazzogna, G. Valle, J. Organomet. Chem. 375
Ž
.
Ž
.
eta, Organometallics 6 1987 834.
1989 167.
x
x
67 M. Carcelli, C. Ferrari, C. Pelizzi, G. Pelizzi, G. Predieri, C.
102 A.I. Tursina, L.A. Aslanov, V.V. Chernyshev, S.V. Medvedev,
Ž
.
Ž
.
Solinas, J. Chem. Soc., Dalton Trans. 1992 2127.
A.V. Yatsenko, Koord. Khim. 11 1985 696.
x
x
68 H. Schumann, B.C. Wassermann, G. Pickardt, Organometallics
103 J.T.B.H. Jastrzebski, P.A. Van der Schaaf, J. Boersma, G. van
Ž
.
12 1993 3051.
Koten, M. de Wit, Y. Wang, D. Heijdenrijk, C.H. Stam, J.
x
Ž
.
69 J.T.B.H. Jastrzebski, E. Wehman, J. Boersma, G. van Koten,
Organomet. Chem. 407 1991 301.

(
)
C. Pettinari et al.rJournal of Organometallic Chemistry 553 1998 345–369
369
w
w
w
w
w
x
104 R. Graziani, U. Casellato, R. Ettorre, G. Plazzogna, J. Chem.
Nitrogen Compounds: The Azoles, Cambridge Univ. Press,
Cambridge, 1976, pp. 346–392.
Ž
.
Soc., Dalton Trans. 1982 805.
x
w
x Ž .
105 K.C. Molloy, M.B. Hossain, D. van der Helm, F.P. Mullins,
114 B.K.S. Lundberg, Acta Crystallogr. 21 1966 901.
115 C. Sandmark, C.-I. Branden, Acta Chem. Scand. 21 1967
Ž
.
w
x
Ž
.
Inorg. Chem. 20 1981 2172.
¨
´
x
106 R.W. Gable, C.L. Raston, G.L. Rowbottom, A.H. White, G.
993.
Ž
.
w
w
w
w
w
x
Winter, J. Chem. Soc., Dalton Trans. 1981 1392.
116 G.B. Jameson, G.A. Rodley, W.T. Robinson, R.R. Gagne,
x
Ž .
C.A. Reed, J.P. Collman, Inorg. Chem. 17 1978 850.
107 R.O. Day, R.R. Holmes, A. Scmidpeter, K. Stoll, L. Howe,
Ž
.
x
117 R.G. Little, K.R. Dymock, J.A. Ibers, J. Am. Chem. Soc. 97
Chem. Ber. 1991 2443.
x
Ž
.
108 S.M.S.V. Doidge-Harrison, R.A. Howie, J.T.S. Irvine, J.L.
1975 4532.
Ž
.
x
118 M. Momenteau, W.R. Scheidt, C.W. Eigenbrot, C.A. Reed, J.
Wardell, Polyhedron 11 1992 2223.
w
w
w
x
Ž
.
Ž .
Am. Chem. Soc. 110 1988 1207.
109 P.J. Wheatley, Acta Crystallogr. 6 1953 369.
110 S. Martinez-Carrera, Acta Crystallogr. 20 1966 783.
111 H. Fujiwara, A.K. Bose, M.S. Manhas, J.M. van der Veen, J.
x
Ž
.
x
119 F. Bonati, A. Burini, B.R. Pietroni, B. Bovio, J. Organomet.
x
Ž .
Chem. 375 1989 147.
Ž
.
x
120 C.R. Johnson, C.M. Jones, S.A. Asher, J.E. Abola, Inorg.
Chem. Soc., Perkin Trans. 2 1979 1327.
w
w
x
x
Ž
.
Ž .
Chem. 30 1991 2120.
112 M.R. Grimmett, Adv. Heterocycl. Chem. 27 1980 151.
113 K. Schofield, M.R. Grimmett, B.R.T. Keene, Heteroaromatic