Reactivity behavior of (hydroxy)diorganotin(IV)methanesulfonates with ionic nucleophiles - Synthesis and structural characterization of novel diorganostannate salts, [R2Sn(μ-OH)(OSO2Me)(ONO 2)]22Bu4N

Article abstract of DOI:10.1016/j.poly.2003.09.010

The reaction of R₂Sn(OH)OSO₂Me [R=n-Pr (1a), or n-Bu (1b)] with one equivalent of Bu₄NNO₃ in CH ₂Cl₂ proceeds via nucleophilic addition of NO ₃^- ion to the Lewis acidic tin center and results in the formation of novel diorganostannates, [R₂Sn(μ-OH)(OSO ₂Me)(ONO₂)]₂2Bu₄N [R=n-Pr (2a), n-Bu(2b)]. The molecular structure of 2b comprises of hydroxy-bridged dimer with monodentate methanesulfonate and nitrate groups bonded to each tin atom. Analogous reactions of the tin precursor, 1b with strong nucleophiles such as Bu₄NX (X=F^-, OAc^-) and RLi (R=n-Bu, Me) favor ionic metathesis pathway involving Sn-OSO₂Me bond cleavage. This approach provides a simple and facile synthetic route for triorganotin oxides, (R₂R′Sn)₂O (R=R′=n-Bu, R=n-Bu, R′=Me).

Full text of DOI:10.1016/j.poly.2003.09.010

Polyhedron 23 (2004) 71–75
www.elsevier.com/locate/poly
Reactivity behavior of (hydroxy)diorganotin(IV)methanesulfonates
with ionic nucleophiles – synthesis and structural
characterization of novel diorganostannate salts,
[
R Sn(l-OH)(OSO Me)(ONO )] 2Bu N
2
2
2 2
4
a,
Ravi Shankar , Mukesh Kumar , Raj K. Chadha , Suraj P. Narula
a
b
c
*
a
Department of Chemistry, Indian Institute of Technology, Hauz Khas, New Delhi 110016, India
b
The Scripps Research Institute, BCC-159, 10555N Torrey Pines Road, La Jolla, CA 92037, USA
c
Department of Chemistry, Punjab University, Chandigarh 160014, India
Received 3 June 2003; accepted 8 September 2003
Abstract
The reaction of R2Sn(OH)OSO2Me [R ¼ n-Pr (1a), or n-Bu (1b)] with one equivalent of Bu4NNO3 in CH2Cl2 proceeds via
ꢀ
nucleophilic addition of NO3 ion to the Lewis acidic tin center and results in the formation of novel diorganostannates, [R2Sn(l-
OH)(OSO2Me)(ONO2)]22Bu4N [R ¼ n-Pr (2a), n-Bu(2b)]. The molecular structure of 2b comprises of hydroxy-bridged dimer with
monodentate methanesulfonate and nitrate groups bonded to each tin atom. Analogous reactions of the tin precursor, 1b with
ꢀ
ꢀ
strong nucleophiles such as Bu4NX (X ¼ F , OAc ) and RLi (R ¼ n-Bu, Me) favor ionic metathesis pathway involving Sn–OSO2Me
0
0
bond cleavage. This approach provides a simple and facile synthetic route for triorganotin oxides, (R2R Sn)2O (R ¼ R ¼ n-Bu,
0
R ¼ n-Bu, R ¼ Me).
Ó 2003 Published by Elsevier Ltd.
Keywords: Diorganostannate; Methanesulfonate; Ionic metathesis; Organotin oxide
1
. Introduction
binding capability of ‘‘tailormade’’ organotin hosts with
high nuclearity tin centers as Lewis acids [4]. This has
led to the isolation of wide structural diversity of
diorganostannate derivatives. In contrast, anionic tin
derivatives bearing functional ligands other than halo-
gen on the tin atom are much less known. The identity
of ÔateÕ complexes, [Bu2SnI2H]Li and [Bu2SnIHBr]MgBr
The property of diorganotin (IV) compounds,
R2SnX2 (X ¼ halogen) to act as Lewis acids has been
frequently utilized to synthesize a large number of tri-
ꢀ
halodiorganostannates, [R2SnX3] [1] as well as tet-
ꢀ
rahalodiorganostannates, [R2SnX4]2
[2]. Recently,
1
19
Tudela et al. [3] have reported solvent dependence on
the formation of these class of compounds. It has been
shown that the reaction of Me SnBr with Et NBr in
generated in situ has been gleaned by
Sn NMR
spectroscopy and their utility in regio/stereoselective
reduction of various enals and aliphatic alkynes has
been reported [5]. The diorganostannates bearing car-
boxylate ligands such as, [R2Sn(O2C)2C5H3NꢁX]Et4N
2
2
4
CHCl /hexane mixture yields [Me SnBr ](Et N) while
2
3
2
4
4
[Me2SnBr3](Et4N) is exclusively formed in water. Ex-
tensive studies have been reported on selective anion
ꢀ
ꢀ
(X ¼ Cl , F ) [6] and [Me2Sn(OAc)3]Me4N [7] have also
been structurally characterized and examined for their
antitumor activity.
*
Corresponding author. Tel.: +91-11-26596421/26591513; fax: +91-
1-26862620/26581102.
In recent years, we have been interested in the de-
velopment of new synthetic strategies for functional
organotin derivatives and reported on the preparation
1
E-mail addresses: shankar@netearth.iitd.ac.in, ravi1@dms.iitd.
ernet.in (R. Shankar).
0
277-5387/$ - see front matter Ó 2003 Published by Elsevier Ltd.
doi:10.1016/j.poly.2003.09.010

72
R. Shankar et al. / Polyhedron 23 (2004) 71–75
and structural characterization of (hydroxy)diorganotin
IV)methanesulfonates, R2Sn(OH)OSO2Me (R ¼ n-Pr,
(
n-Bu, etc.) [8]. The reaction chemistry of these bifunc-
tional tin compounds has attracted our attention. It has
been demonstrated that the selective dehydration reac-
tion involving Sn–OH group with carboxylic acids re-
sults in the isolation of diorganotin carboxylates [9],
which are not accessible by classical route. Another
interesting aspect concerns the reactivity of these tin
precursors towards the ionic nucleophiles. In the pres-
ent work, preliminary investigations on this aspect
have been undertaken. While the reaction of 1a or 1b
with Bu NNO results in the isolation of novel diorg-
4
3
anostannate derivatives, 2a or 2b, the use of strong
ꢀ
ꢀ
nucleophiles such as Bu4NX (X ¼ F , OAc ) and RLi
(
R ¼ n-Bu, Me) favor ionic metathesis reaction involving
Sn–OSO2Me bond cleavage. The results obtained from
these studies are reported herein.
2
. Results and discussion
The synthesis of [R2Sn(l-OH)(OSO2Me)(ONO2)]2
Bu4N [R ¼ n-Pr (2a), n-Bu (2b)] is accessible from the
2
Fig. 1. ORTEP view of one independent molecule of 2b, showing 30%
probability ellipsoids. Hydrogen atoms have been omitted for clarity.
reaction of (hydroxy)diorganotin methanesulfonates (1a
or 1b) with one equivalent of tetra-n-butylammonium
nitrate (Eq. (1)). These compounds are moderately
sensitive to moisture and are soluble in common organic
solvents such as chloroform, dichloromethane, metha-
nol, acetonitrile, etc.
Table 1
Summary for crystallographic data for 2ba
Empirical formula
Formula weight
T (°C)
k (A)
Crystal system
Space group
C
648.48
25
H
58
N
2
O
7
SSn
173(2) K
0.71073
triclinic
2
R
2
SnðOHÞOSO
RT=8–10 h
2
Me þ 2Bu
4
NNO
3
ꢀ
ꢀ
ꢀꢀꢀ! ½R
2
Snðl-OHÞðOSO
R ¼ n-Pr ð2aÞ; n-Bu ð2bÞ
2
MeÞðONO
2
Þꢂ 2Bu
4
N
2
ꢁ
1
P1 (no. 2, Ci )
11.9775(18)
13.610(2)
22.857(3)
81.360(2)
75.527(3)
67.153(2)
3318.8(9)
4
ꢀ
ð1Þ
a (A)
ꢀ
b (A)
ꢀ
c (A)
The single crystals of 2b suitable for X-ray structure
a (°)
b (°)
c (°)
V (A )
Z
were obtained upon cooling solution of the compound
in dichloromethane at 4 °C for several days. The
compound crystallizes with two independent molecules
in the unit cell of which only one is shown in Fig. 1.
The relevant crystal data are given in Table 1, while
selected bond distances and angles are given in Table 2.
The anion in each molecule adopts a centrosymmetric
hydroxy-bridged dimeric structure with highly distorted
octahedral geometry around each tin atom. The SnO4
coordination sphere formed by two bridging OH, a
monodentate methanesulfonate and a nitrate group is
planer (360° ꢃ 1). Principle differences between the two
molecules in the unit cell appear in the Sn–O (me-
thanesulfonate and nitrate) bond distances and O–Sn–
O/C–Sn–C angles. A comparison of these metrical
ꢀ
3
ꢀ
3
qcalcd (Mg m
)
1.298
0.872
ꢀ
1
l (mm
Final R indices
)
R
wR
1
¼ 0:0735
½
I > 2rðIÞꢂ
2
¼ 0:1938
R indices (all data)
P
R ¼ 0:1250, wR ¼ 0:2241
1
2
P
P
P
a
2
o
2
c
2
2
o
2
1=2
R ¼ð kkF kꢀkF kk= kF kÞ,wR ¼½ wðF ꢀF Þ = ½wðF Þ ꢂꢂ
1
o
c
o
2
,
P
2
o
2
c
2
1=2
s ¼ ½ wðF ꢀ F Þ =n ꢀ pꢂ
.
ꢀ
O(2B) ¼ 2.552(7) A] and suggests appreciable ionic
character. The angle C(5A)–Sn(1A)–C(1A) ¼ 159.6(3)°/
C(5B)–Sn(1B)–C(1B) ¼ 153.3(4)° is much larger than
observed in the tin precursor 1b [C–Sn–C ¼ 151.4(3)°].
Secondary interactions such as intramolecular hydro-
parameters with those of the precursor [Sn–O
ꢀ
(
elongation of Sn–O (methanesulfonate) bond distance
methanesulfonate) ¼ 2.410(4) A] [8] reveals significant
ꢀ
gen bonding [O(3A)ꢁ ꢁ ꢁH–O(1A) ¼ 2.694 A, O(3B)ꢁ ꢁ ꢁH–
ꢀ
in the stannate [Sn(1A)–O(2A) ¼ 2.451(6)/Sn(1B)–
O(1B) ¼ 2.780 A] as well as intermolecular C–Hꢁ ꢁ ꢁO

R. Shankar et al. / Polyhedron 23 (2004) 71–75
73
Table 2
ꢀ
a
Selected bond lengths (A) and angles (°) for the two independent molecules of 2b
Bond lengths
Sn(1A)–C(1A)
Sn(1A)–O(1A)
Sn(1A)–C(5A)
Sn(1A)–O(5A)
Sn(1A)–O(2A)
Sn(1A)–O(1A)#1
2.139(8)
2.130(5)
2.117(8)
2.418(5)
2.451(6)
2.118(5)
Sn(1B)–C(1B)
Sn(1B)–O(1B)
Sn(1B)–C(5B)
Sn(1B)–O(5B)
Sn(1B)–O(2B)
Sn(1B)–(1B)#2
2.150(9)
2.136(5)
2.105(9)
2.383(6)
2.552(7)
2.104(6)
Bond angles
C(5A)–Sn(1A)–C(1A)
O(1A)#1–Sn(1A)–O(1A)
O(1A)–Sn(1A)–O(5A)
O(5A)–Sn(1A)–O(2A)
O(1A)#1–Sn(1A)–O(2A)
159.6(3)
C(5B)–Sn(1B)–C(1B)
O(1B)#2–Sn(1B)–O(1B)
O(1B)#2–Sn(1B)–O(5B)
O(5B)–Sn(1B)–O(2B)
O(1B)–Sn(1B)–O(2B)
153.3(4)
71.8(2)
74.95(18)
130.95(18)
82.4(2)
71.8(3)
74.2(2)
136.6(2)
77.5(2)
a
#
1 ꢀx þ 2; ꢀy þ 1; ꢀz, #2 ꢀx; ꢀy þ 2; ꢀz þ 1.
ꢀ
A,
interaction
[C(11B)–H(11D)ꢁ ꢁ ꢁO(7A) ¼ 2.506
2Bu SnðOHÞOSO Me þ 2Bu NX
2
2
4
ꢀ
C(15A)–H(15B)ꢁ ꢁ ꢁO(7B) ¼ 2.458 A] have also been
observed. Similar interactions have been previously
reported in organotin carboxylates derived from ferr-
ocenyl carboxylic acid [10].
!
½Bu
2
SnðXÞꢂ O þ 2Bu
4
NOSO
2
Me þ H
2
O
2
ðX ¼ F; OAcÞ
ð2Þ
ð3Þ
2
Bu SnðOHÞOSO Me þ 2RLi
The IR spectra (KBr) of 2a and 2b reveal two bands
at 1485–1490 and 1384–1388 cm 1 due to maNO2 and
m NO , respectively, and suggest unidentate coordina-
2
2
ꢀ
! ðBu RSnÞ O þ 2LiOSO Me þ H O
2
2
2
2
s
2
ðR ¼ n-Bu; MeÞ
tion mode of the nitrate group [11]. The strong ab-
sorptions due to mSO3 mode appear at 1205–1210 and
The identity of these products has been confirmed by
1
119
ꢀ
1
comparison of IR, H, and Sn NMR spectral data
with those of the known compounds previously reported
in literature [14].
1
050–1060 cm . The absence of additional splitting of
these bands may be attributed to the monodentate
character of methanesulfonate group [12]. 1H NMR
spectrum of each compound identifies Pr2Sn/Bu2Sn,
A final comment concerns the formation of the stan-
ꢀ
nates, 2a and 2b. Complexation of the NO3 ion to the
Bu4N and SMe groups in 1:1:1 integrated ratio and
conforms to the structural composition. 119Sn NMR
spectra in CDCl show four distinct signals spanning a
tin center of 1a or 1b can be rationalized by considering
coordinative dissociation of bridging bidentate me-
thanesulfonate in the tin precursors [8]. It appears that
3
broad chemical shift range and appear at d )155, )159,
ꢀ
ꢀ
the nucleophilicity of NO3 and MeSO3 ions being
comparable [15] inhibits the ionic metathesis pathway.
Nevertheless, the use of organometallic reagents such as
RLi may also be of significant synthetic utility in the
formation of mixed triorganotin oxides. This aspect is
presently being investigated in our laboratory.
)
2
191, )234 (for 2a) and )157, )159, )194, )234 (for
b). The Sn NMR chemical shift values and spectral
1
19
intensity of the signals between d )155 and )195 show a
close resemblance to those of parent tin precursors, 1a
and 1b, while the appearance of a new upfield signal at d
)
234 may be ascribed to the stannates (2a and 2b).
These results coupled with the lack of J(119Sn–O–117Sn)
coupling may suggest a fast equilibrium in solution be-
tween the precursor tin compound and the product.
Such phenomena have been reported in a few studies
related to the formation of stannate derivatives [13]. No
change in the d 119Sn NMR values was observed upon
addition of another equivalent amount of Bu4NNO3 to
2
3. Experimental
All reactions were conducted in an inert atmosphere
of nitrogen. Solvents were dried using standard tech-
niques (dichloromethane and n-hexane over P O , di-
1a or 1b suggesting that the tin precursor binds only one
ꢀ
NO3 ion.
2
5
ethyl ether over sodium benzophenone). Glassware was
dried in an oven at 110–120 °C and further flame dried
under vacuum prior to use. The precursors, (hydroxy)di-
n-propyl/di-n-butyltin(IV)methanesulfonates [8] and di-
n-propyltin oxide [16] were prepared using literature
methods, while the reagents such as Bu NX (X ¼ NO ,
Nucleophilicity of the anionic reagents has been
found to substantially alter the reaction chemistry of the
tin precursors. This is evident by studying the reactions
of 1b with Bu4NX (F, OAc) or RLi (n-Bu, Me). These
reactions invariably proceed via an ionic metatheses
pathway involving the cleavage of Sn–OSO2Me bond.
The products obtained in these reactions are shown as:
4
3
F, OAc) and RLi (R ¼ Bu, Me) were obtained com-
1
13
119
mercially (Aldrich). H, C and
Sn NMR spectra

74
R. Shankar et al. / Polyhedron 23 (2004) 71–75
were recorded on Bruker DPX-300 at 300, 75.46 and
1
3.2. Reactions of (hydroxy)di-n-butyltin methanesulfo-
ꢀ
11.88 MHz, respectively. H and 13C chemical shifts
nate with Bu
NX (X ¼ F , OAc )
ꢀ
1
4
are quoted with respect to the residual protons of
the solvent, while 119Sn NMR data are given using te-
tramethyltin as internal standard. The IR spectra were
recorded on Nicolet prot ꢂe g ꢂe 460 E.S.P. spectropho-
tometer using KBr optics. Elemental analysis (C, H
and N) was performed on a Perkin–Elmer model
To a stirred suspension of (hydroxy)di-n-butyltin
methanesulfonate, 1b (0.62 g, 1.79 mmol) in dichlo-
romethane was added Bu4NF (1.79 ml (1.0 M/THF),
1.79 mmol). The resulting clear solution was stirred
for 8–10 h at room temperature. Thereafter the reac-
tion mixture was concentrated under vacuum and di-
ethyl ether was added to precipitate a white solid
identified as tetra-n-butyl ammonium methanesulfonate,
Bu4NOSO2Me. Solvent was evaporated from the ether
solution to afford [Bu2Sn(F)]2O as a white solid. The
2400CHN elemental analyzer. Tin was estimated gravi-
metrically [17].
3.1. Reactions of (hydroxy)diorganotin methanesulfonate
with tetrabutylammonium nitrate
reaction of 1b (0.62 g, 1.79 mmol) with Bu NOAc (0.53
4
g, 1.79 mmol) was performed by following a similar
procedure as above. n-Hexane was added to precipitate
the salt Bu4NOSO2Me which was filtered and dried
under vacuum. The compound [Bu2Sn(OAc)]2O was
isolated from the concentrated hexane solution as a
white solid.
To a stirred suspension of (hydroxy)di-n-propyl-
tin(IV)methanesulfonate (0.69 g, 2.16 mmol) or (hy-
droxy)di-n-butyltin(IV)methanesulfonate (0.75 g, 2.16
mmol) in dichloromethane (ꢄ50 ml) was added a solu-
tion of Bu4NNO3 (0.65 g, 2.16 mmol) in the same sol-
vent. The clear reaction mixture was stirred for 12–15 h.
at room temperature. The resulting solution was con-
centrated under vacuum and n-hexane was added. A
white solid, thus obtained in each case was filtered and
dried in vacuum.
3
.2.1. Bu NOSO Me
4 2
1
Yield: (45%), H NMR (CDCl ): d 3.31 (t, 8H, NCH ),
3
2
2
.75 (s, 3H, SMe), 1.66 (m, 8H, NCH CH ), 1.44 (m, 8H,
2 2
ꢀ1
N(CH2)2CH2) 1.01 (t, 12H, CH3). IR (KBr, cm ): 2960,
932 (mCH), 1240, 1193, 1058 (mSO3), 784 (SMe). Anal.
2
Calc. for C17H39NO3S: C, 60.53; H, 11.57; N, 4.15;
Found: C, 61.01; H, 11.43; N, 4.21%.
3
.1.1. [n-Pr
2
2 2 2 4
Sn(l-OH)(OSO Me)(ONO )] 2Bu N (2a)
1
Yield: (85%), m.p. 80–83 °C. H NMR (CDCl3): d
.33 (t, 8H, NCH ), 2.77 (s, 3H, SMe), 1.78 (m, 16H,
3
Sn(CH ) + NCH CH ), 1.50 (m, 8H, N(CH ) CH ),
1
2
3
.2.2. [Bu Sn(F)] O
2 2
2
2
2
2
2 2
2
Yield: (41%), m.p. 137–140 °C (Lit. 140 °C). 1H
NMR (CDCl ): d 0.92 (t, 6H, CH ), 1.20 (m, 8H,
1
3
1
.01 (t, 18H, Sn(CH ) CH + N(CH ) CH ). C{ H}
2 2 3 2 3 3
3
3
NMR (CDCl3): 58.3 (NCH2), 39.2 (SMe), 29.2
SnCH2), 18.1 (SnCH2CH2), 12.2 (Sn(CH2)2CH3 +
1
19
(CH2)2CH3), 1.54 (m, 4H, SnCH2).
Sn NMR
(
ꢀ
1
(CDCl3): d )160. IR (KBr, cm ): 2959, 2928, 2857
N(CH2)3CH3), 23.5 (NCH2CH2), 19.3 N(CH2)2CH2.
1
19
(mCH), 660 (mSn–O–Sn). Anal. Calc. for C16H36OF2Sn2:
C, 36.78; H, 6.89. Found: C, 36.60; H, 6.75%.
Sn NMR (CDCl3): d )155, )159, )191, )234. IR
ꢀ
1
(
KBr, cm ): 3420 (mOH), 1487, 1386 (mNO2), 1209,
1
C H N O SSn: C, 44.37; H, 8.68; N, 4.50; Sn, 19.29.
Found: C, 44.10; H, 8.75; N, 4.61; Sn, 19.91%.
054 (mSO ), 784 (SMe). Anal. Calc. for
3
3
.2.3. [Bu Sn(OAc)] O
2 2
2
3
54
2
7
1
Yield: (51%), m.p. 52–53 °C (Lit. 54 °C). H NMR
(CDCl ): d 1.89 (s, 3H, OAc), 0.86 (t, 6H, CH ), 1.30 (m,
3
3
19
1
8
H, (CH2)2CH3), 1.57 (m, 4H, SnCH2).
Sn NMR
ꢀ
1
3
.1.2.[n-Bu
2
Sn(l-OH)(OSO
2
Me)(ONO
1
2
)]
2
2Bu
4
N(2b)
(CDCl3): d )215, )226. IR (KBr, cm ): 2961, 2926,
2870 (mCH), 1636, 1559 (maCO2), 1372 (msCO2), 639
(mSn–O–Sn). Anal. Calc. for C20H42O5Sn2: C, 39.86; H,
6.97. Found: C, 39.60; H, 6.74%.
Yield: (90%), m.p. 72–75 °C. H NMR (CDCl3): d
.33 (t, 8H, NCH2), 2.77 (s, 3H, SMe), 1.65 (m, 16H,
3
Sn(CH2)2 + NCH2CH2), 1.45 (m, 12H, N(CH2)2CH2 +
Sn(CH ) CH ), 1.03 (t, 12H, N(CH ) CH ), 0.93 (t, 6H,
2
2
2
2 3
3
1
3
1
Sn(CH ) CH ).
(
C{ H} NMR (CDCl ):
d
58.3
NCH ), 39.2 (SMe), 26.5 (SnCH ), 23.5 (SnCH CH +
3.3. Reactions of (hydroxy)di-n-butyltin methanesulfo-
nate (1b) with RLi (R ¼ n-Bu, Ph)
2
3
3
3
2
2
2
2
NCH2CH2), 18.1 (Sn(CH2)2CH2), 12.2 (Sn(CH2)2
CH3 + N(CH2)3CH3, 23.5 (NCH2CH2), 19.3 (Sn(CH2)2
To a stirred solution of 1b (0.75 g, 2.16 mmol) in
diethyl ether (ꢄ75 ml) was added n-BuLi (3.45 ml, 1.6
M/hexane, 2.16 mmol) or MeLi (2.16 ml, 1.0 M/THF,
2.16 mmol) at 25 °C. The reaction mixture was stirred
for 12 h and subsequently hydrolyzed by 25 ml of water.
The organic layer was extracted in each case and kept on
anhydrous sodium sulfate. Evaporation of solvent ether
CH2 +
N(CH2)2CH2),
13.2
(Sn(CH2)3CH3 +
1
19
N(CH2)3CH3).
Sn NMR (CDCl3): d )157, )159,
ꢀ
1
)
194, )234. IR (KBr, cm ): 3400 (mOH), 1487, 1384
(
C H N O SSn: C, 46.15; H, 8.92; N, 4.30; Sn, 18.46.
mNO ), 1210, 1058 (mSO ), 784 (SMe). Anal. Calc. for
2
3
2
5
58
2
7
Found: C, 46.91; H, 8.33; N, 4.21; Sn, 18.01%.

R. Shankar et al. / Polyhedron 23 (2004) 71–75
75
gave (Bu3Sn)2O or (Bu2Me)2SnO as colorless viscous
liquids.
Acknowledgements
M.K. is grateful to CSIR New Delhi for senior re-
search fellowship.
3
.3.1. (Bu Sn) O
3 2
Yield: (55%): b.p. 205–210 °C/10 mm (Lit. 210–214
1
°
C/10 mm). H NMR (CDCl ): d 0.90 (t, 6H, CH ), 1.37
3 3
(
(
(
m, 8H, (CH2)2CH3), 1.65 (m, 4H, SnCH2). 119Sn NMR
References
CDCl3): d 85.6. IR (KBr, cm 1): 2961, 2926, 2870
ꢀ
mCH), 689 (mSn–O–Sn). Anal. Calc. for C24H54OSn2: C,
[
[
[
1] E.M. Garcia, A.G. Sanchez, A. Castineiras, J.S. Casas, J. Sordo,
J. Organomet. Chem. 469 (1994) 41.
2] J. Ouyang, Y. Zu, L.E. Khoo, J. Organomet. Chem. 561 (1998)
4
8.16; H, 9.03. Found: C, 47.95; H, 9.21%.
1
43.
3
.3.2. (Bu MeSn) O
2
2
3] D. Tudela, M. Diaz, D.A. Alvaro, J. Ignacic, L. Seijo, V.K.
Belsky, Organometallics 20 (2001) 654 (and references cited
therein).
Yield: (50%): b.p. 180–185 °C/10 mm. 1H NMR
(
CDCl ): d 0.91 (t, 6H, CH ), 1.40 (m, 8H, (CH ) CH ),
3 3 2 2 3
119
1
.71 (m, 4H, SnCH2), 1.85 (s, 3H, SnCH3). Sn NMR
[4] (a) P.D. Beer, P.A. Gale, Angew. Chem. Int. Ed. 40 (2001) 486;
(b) M. Shulte, M. Schurmann, K. Jurkschat, Chem. Eur. J. 7
CDCl3): d 95.0. IR (KBr, cm 1): 2963, 2927, 289 (CH),
80 (mSn–O–Sn). Anal. Calc. for C18H42OSn2: C, 42.02;
H, 8.17. Found: C, 42.11; H, 8.10%.
ꢀ
(
6
(
(
2001) 347;
c) R. Altmann, O. Gausset, D. Horn, K. Jurkschat, M.
Schurmann, M. Fontani, P. Zanello, Organometallics 19 (2000)
30;
4
3
.4. X-ray crystallography
(d) F.P. Schmidtchen, M. Berger, Chem. Rev. 97 (1997) 1609.
5] (a) T. Suwa, I. Shibata, A. Baba, Organometallics 18 (1999) 3965;
[
[
(
b) I. Shibata, T. Suwa, A. Baba, J. Am. Chem. Soc. 123 (2001)
101.
A colorless, block shaped crystal was mounted along
4
with the largest dimension and data were collected on a
Bruker SMART APEX diffractometer equipped with a
molybdenum sealed tube and a highly oriented graphite
monochromator. There were no systematic absences in
6] (a) R. Willem, M. Biesemans, M. Boualam, A. Delmotte, A. EI
Khloufi, M. Gielen, Appl. Organomet. Chem. 7 (1993) 311;
(b) S.W. Ng, V.G. Kumar Das, J. Holecek, A. Lycka, M. Gielen,
M.G.B. Drew, Appl. Organomet. Chem. (1997) 1139.
ꢁ
[7] T.P. Lockhart, J.C. Calabrese, F. Davidson, Organometallics 6
1987) 2479.
the data, therefore space group P1 was assumed and
(
8] S.P. Narula, S. Kaur, R. Shankar, S. Verma, P. Venugopalan,
later confirmed by successful refinement of the structure.
The structure was solved by direct methods using
SHELXTL-PC [18,19]. All non-hydrogen atoms were re-
fined anisotropically by the full matrix least-square
method. The function was minimized to
kFckÞ . Hydrogen atoms were included in the ideal po-
sition with fixed isotropic U values equal to 1.2 times
that of the atom they are attached to. A weighting
[
S.K. Sharma, R.K. Chadha, Inorg. Chem. 38 (1999) 4777.
[9] R. Shankar, M. Kumar, S.P. Narula, R.K. Chadha, J. Organo-
met. Chem. 671 (2003) 35.
P
[
[
10] V. Chandrasekhar, S. Nagendran, S. Bansal, A.W. Cordes, A. Vij,
Organometallics 21 (2002) 3297.
wðkFokꢀ
2
11] K. Nakamoto, Infrared and Raman Spectra of Inorganic and
Coordination Compounds, 5th ed., Wiley, New York, 1997, p. 87.
[12] (a) P.A. Yeats, J.R. Sams, F. Aubke, Inorg. Chem. 11 (1972)
2634;
2
2
2
scheme of the form w ¼ 1=½r ðF Þþ ðaPÞ þ bPꢂ with
o
(
b) E. Hochberg, E.H. Abott, Inorg. Chem. 117 (1978) 506.
a ¼ 0:1185 and b ¼ 0:00 was used. (P is defined as
2
o
2
c
[13] D. Dakternieks, H. Zhu, Organometallics 11 (1992) 3820.
[14] (a) A.G. Davies, L. Smith, P.J. Smith, W. Mc Farlane, J.
maxðF ; 0Þ þ 2F =3.) An extinction correction was also
applied. The refinement converged to the R indices given
in Table 1. All calculations were done on an IBM
compatible PC using Windows-NT operating system.
Organomet. Chem. 29 (1971) 245;
(b) Y. Maeda, R. Okawara, J. Organomet. Chem. 10 (1967) 247;
(c) D.C. Gross, Inorg. Chem. 28 (1989) 2355;
(
(
d) S.J. Blunden, R. Hill, J. Organomet. Chem. 333 (1987) 317;
e) Wm.J. Considine, J.J. Ventura, B.G. Kushlefsky, A. Ross, J.
Organomet. Chem.1 (1964) 299.
4
. Supplementary data
[
[
15] F.A. Carey, R.J. Sundberg, Advanced Organic Chemistry (Part
A), 4th ed., Kluwer Academic/Plenum, New York, 2000, p. 291.
16] R.K. Ingham, S.D. Rosenberg, H. Gilman, Chem. Rev. 60 (1960)
Crystallographic data for the structural analysis have
been deposited with the Cambridge Crystallographic
Data Center, CCDC No. 204117 for compound 2b.
Copies of this information may be obtained free of
charge from The Director, CCDC, 12 Union Road,
Cambridge CB2 1EC, UK (Fax: +44-1223-336033; E-
mail: deposit@ccdc.cam.ac.uk or www: http://www.
ccdc.cam.ac.uk).
4
59.
[17] A.I. Vogel, Textbook of Quantitative Chemical Analysis, 5th ed.,
Longman, London, 1989, p. 474.
[
18] SMART (Ver 5.6). Software for data collection on CCD Detector
System. Bruker X-ray Analytical Instruments, Madison, WI,
1
995.
[
19] SHELXTL-PC. (Ver 5.1) G.M. Sheldrick, Bruker X-ray Analytical
Instruments, Inc. Madison, WI, 1990.