Role of Y,C,Y-chelating ligands in control hydrolysis of diorganotin compounds

Article abstract of DOI:10.1021/om8002015

The potential use of Y,C,Y-chelating ligands in control hydrolysis of diorganotin(IV) compounds of general formula L^1,2SnPhX₂ (L¹ = 2,6-(Me₂NCH₂)₂C ₆H₃, L²

Full text of DOI:10.1021/om8002015

Organometallics 2008, 27, 3743–3747
3743
Role of Y,C,Y-Chelating Ligands in Control Hydrolysis of
Diorganotin Compounds†
Blanka Kasˇna´,‡ Libor Dosta´l,‡ Robert Jira´sko,§ Ivana Císarˇová,| and Roman Jambor*,‡
Department of General and Inorganic Chemistry and Department of Analytical Chemistry, UniVersity of
ˇ
Pardubice, na´m. Cs. legiı´ 565, CZ-532 10, Pardubice, Czech Republic, and Charles UniVersity in Prague,
Faculty of Natural Science, HlaVoVa 2030, 128 40 Praha 2, Czech Republic
ReceiVed March 4, 2008
The potential use of Y,C,Y-chelating ligands in control hydrolysis of diorganotin(IV) compounds of
general formula L1,2SnPhX2 (L1 ) 2,6-(Me2NCH2)2C6H3, L2 ) 2,6-(MeOCH2)2C6H3, and X ) Cl, CF3SO3,
and [1-CB11H12]) is reported. The hydrolysis of moisture-sensitive compounds L1SnPh(OTf)2 (3) and
L2SnPh(OTf)2 (4) gave organotin(IV) cations {[L1SnPh(OH2)(OTf)]+[OTf]-} (5) and {[L2SnPh-
(OH2)(OTf)]+[OTf]-} (6). Reported is also the preparation of diorganotin(IV) cations {[L1SnPhCl]+
[1-CB11H12]-} (7) and {[L2SnPhCl]+ [1-CB11H12]-} (8) and the isolation of [PhL2Sn-µ-(OH)2-SnL2Ph]2+
2*[1-CB11H12]- (9), the final hydrolytic product of 8. The products were characterized by 1H, 11B, 13C,
and 119Sn NMR and IR spectroscopy, ESI/MS, and elemental analyses, and the structures of compounds
3 and 6 were determined by X-ray diffraction studies.
In general, organotin cations are well-known as species with
pronounced Lewis acidic character of the central tin atom and
are important intermediates in hydrolysis of organotin halides,
a key step in the preparation of stannoxanes.6 However, this
hydrolysis process is usually complicated to some extent, leading
to a variety of the hydrolysis products like organotin oxides,
hydroxides, and oxide-hydroxides. The hydrolysis of organotin
halides has been discussed to occur through the intermediacy
of hydrated organotin cations such as [R2Sn(OH2)4]2+ or
analogous organotin compounds.7 Recent reports showed the
preparation and structural characterization of such species {[n-
Bu2Sn(OH2)4]2+[2,5-Me2C6H3-SO3-]2},8a {[n-Bu2Sn(OH2)3-
[µ-L]-n-Bu2Sn(OH2)3]2+-[L]2-}(L)1,5-C6H10(SO3-)2),8b{[Me2Sn-
(OH2)4]2+[X-]2} (X ) 1,1,3,3-tetraoxo-1,3,2-benzodithiazide),8c
and {[R2Sn(OH2)2(OPPh3)2]2+[CF3SO3-]2} (R )Me, n-Bu).8d
These compounds can act as the precursors of hydrolysis to
effort the products containing Sn-OH or Sn-O bonds.
Introduction
The long history investigation of organotin cations showed
a relatively large number of triorganotin cations1 (the trimeth-
yltin cation hydrates and ammoniates have been known since
1960s),2 while the preparation of diorganotin dications stabilized
by coordination with alkynylborates and phosphine oxide was
reported recently.3 One of the most promising areas of organotin
cations is the chemistry of cationic clusters. The Sn12 dications
[(RSn)12O14(OH)6]2+ have received attention in view of nano-
building blocks for sol-gel-derived hybrid materials,4 and
recently prepared Sn2 dications [R2(H2O)Sn-µ-(OH)2-Sn(H2O)
R2]2+ 2Y- (Y ) CF3SO3, C8F17SO3) were shown to be very
efficient alcohol acetylation and C-C coupling bond catalysts.5
† Dedicated to Professor Jaroslav Holecˇek on the occasion of his 75th
birthday.
* To whom correspondence should be addressed. Fax: + 420 466037068.
Recently, we have noted the simple preparation of tetraor-
ganodistannoxane [{2,6-(t-BuOCH2)2C6H3}2Sn(OH)]2O contain-
ing O,C,O-chelating ligand.9 To explore the field of potential
use of Y,C,Y-chelating ligands in control hydrolysis of orga-
notin(IV) compounds, diorganotin(IV) compounds of general
E-mail: roman.jambor@upce.cz.
‡ Department of General and Inorganic Chemistry, University of Pardubice.
§ Department of Analytical Chemistry, University of Pardubice.
| Charles University in Prague.
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10.1021/om8002015 CCC: $40.75
2008 American Chemical Society
Publication on Web 07/12/2008

3744 Organometallics, Vol. 27, No. 15, 2008
Kasˇna´ et al.
Chart 1
formula L1,2SnPhX2, where L1 ) 2,6-(Me2NCH2)2C6H3, L2 )
2,6-(MeOCH2)2C6H3, and X ) Cl, CF3SO3 (hereafter OTf), and
[1-CB11H12] were prepared (Chart 1). The central tin(IV) atom
in these compounds possess different Lewis acidity depending
on group X. As the result of these variances, the isolation of
hydrated organotin(IV) cations {[L1,2SnPh(OH2)(OTf)]+
[OTf]-} as well as [PhL2Sn-µ-(OH)2-SnL2Ph]2+ 2*[1-CB11-
H12]- as the final hydrolytic product is reported.
Figure 1. General view (ORTEP) of a molecule showing 30%
probability displacement ellipsoids and the atom-numbering scheme
for 3. The hydrogen atoms are omitted for clarity. Selected bond
distances(Å)andangels(deg):Sn(1)-O(11)2.2187(14);Sn(1)-O(21)
2.2368(15); Sn(1)-C(11) 2.0745(18); Sn(1)-C(21) 2.1265(18);
Sn(1)-N(1) 2.3850(16); Sn(1)-N(2) 2.4020(17); N(2)-Sn(1)-N(2)
153.35(5);O(11)-Sn(1)-O(21)174.49;N(2)-Sn(1)-O(21)94.41(6);
N(2)-Sn(1)-O(11) 86.48(6); C(11)-Sn(1)-C(21) 178.64(8).
Results and Discussion
The treatment of L1,2SnPhCl2 (L1 (1) and L2 (2)) with 2 equiv
of AgOTf led to the preparation of moisture-sensitive com-
pounds L1SnPh(OTf)2 (3) and L2SnPh(OTf)2 (4) (eq 1).
coordinated to the tin atom by strong intramolecular interactions
Sn-N (Sn(1)-N(1) 2.3850(16) Å and Sn(1)-N(2) 2.4020(17)Å).
The Sn1-O11 and Sn1-O21 distances 2.2187(14)Å and
2.2368(15)Å (involving OTf groups) being longer than
Σ
covSn-O (2.13Å)12 indicate the presence of strong intramo-
L1,2PhSnCl2 + 2AgOTf f L1,2PhSn(OTf)2 + 2AgCl (1)
L1(3), L2(4)
lecular interactions Sn-O rather than a covalent bond. Both
OTf groups are, however, bound more tightly to the tin than in
[n-Bu2Sn(µ-OH)-(OH2)(O3SCF3)]2 (Sn-O 2.622(4) Å).13
The exposition of 3 and 4 to air resulted in the isolation of
air- and moisture-stable organotin(IV) cations {[L1SnPh(OH2)-
(OTf)]+ [OTf]-} (5) and {[L2SnPh(OH2)(OTf)]+ [OTf]-} (6)
(eq 2).
The values of δ(119Sn) found for 3 (-320.1 ppm) and 4
(-401.3 ppm) indicate the presence of a six-coordinated central
tin atom.10 The upfield shift of δ(119Sn) compared to the starting
1 (-212.8 ppm) and 2 (-208.8 ppm) suggests an important
1
increase of Sn-Y bond strength in 3 and 4. The H NMR
spectroscopy at various temperatures (range of 300-170 K)
revealed the presence of one set of sharp signals of CH2 and
CH3 protons indicating that both CH2Y groups are coordinated
mutually in trans positions giving thus a symmetrical octahedral
arrangement at the central tin atom in 3 and 4 having also both
C atoms and O atoms of both OTf groups mutually in trans
positions. The IR spectrum showed the presence of covalently
bound OTf groups in monodentate fashion.11
The X-ray structure analysis of 3 proved these assumptions,
and the structure is shown in Figure 1 together with selected
bond lengths and angles. The structure of compound 3 showed
a distorted octahedral arrangement comprising two nitrogen
atoms (N1 and N2) of the L1 ligand, two oxygen atoms of OTf
groups (O11 and O21), and two carbon atoms from the L1 ligand
C(21) and phenyl group C(11) arranged in trans positions with
respect to each other (Figure 1). Both nitrogen atoms are
L1,2SnPh(OTf)2 air moisture8 [L1,2SnPh(OH2)OTf]+[OTf]-
L1(3), L2(4)
L1(5), L2(6)
(2)
The ionic nature of 5 and 6 has been mainly established by
solution119Sn NMR spectroscopy and solution IR spectroscopy.
The values of δ(119Sn) (-303.6 ppm for 5, - 356.4 ppm for 6)
are shifted downfield compared to those found in molecular
compounds 3 (-320.1 ppm) and 4 (-401.3 ppm) and indicate
the presence of a six-coordinated central tin atom.10 The
downfield shift of δ(119Sn) in 5 and 6 is characteristic of the
ionization process in organotin compounds.14 The values of
(12) Huheey, J. E.; Keiter, E. A.; Keiter, R. L. Inorganic Chemistry:
Principles of Structure and ReactiVity, 4th ed.; Harper Collins College
Publishers: New York, 1993; p 292.
(13) Sakamoto, K.; Ikeda, H.; Akashi, H.; Fukuyama, T.; Orita, A.;
Otera, J. Organometallics 2000, 19, 3242.
(14) (a) Kasˇna´, B.; Jambor, R.; Dosta´l, L.; Kolárˇova´, L.; Císarˇová, I.;
Holecˇek, J. Organometallics 2006, 25, 148. (b) Kasˇna´, B.; Jambor, R.;
Dosta´l, L.; Ru˚žicˇka, A.; Císarˇová, I.; Holecˇek, J. Organometallics 2004,
23, 5300.
(10) (a) Holecˇek, J.; Na´dvorn´ık, M.; Handlírˇ, K.; Lycˇka, A. J. Orga-
nomet. Chem. 1986, 315, 299. (b) Holecˇek, J.; Na´dvorn´ık, M.; Handlírˇ, K.;
Lycˇka, A. Z. Chem. 1990, 30, 265. (c) Holecˇek, J.; Na´dvorn´ık, M.; Handlírˇ,
K.; Lycˇka, A. J. Organomet. Chem. 1983, 241, 177. (d) Holecˇek, J.;
Na´dvorn´ık, M.; Handlírˇ, K.; Lycˇka, A. Collect. Czech. Chem. Commun.
1990, 55, 1193. (e) Lycˇka, A.; Holecˇek, J.; Schneider, B.; Straka, J. J.
Organomet. Chem. 1990, 389, 29.
(11) Kasˇna´, B.; Jambor, R.; Dosta´l, L.; Císarˇová, I.; Holecˇek, J. J.
Organomet. Chem. 2007, 691, 1554.
(15) Chandrasekhar, V.; Singh, P.; Gopal, K. Organometallics 2007,
26, 2833.

Hydrolysis of Diorganotin Compounds
Organometallics, Vol. 27, No. 15, 2008 3745
Figure 2. General view (ORTEP) of a molecule showing 30%
probability displacement ellipsoids and the atom-numbering scheme
for 6. Hydrogen atoms have been omitted for clarity. Selected bond
distances (Å) and angles (deg): Sn(1)-O(1) 2.2363(17); Sn(1)-O(11)
2.2305(16); Sn(1)-O(12) 2.2561(16); Sn(1)-O(31) 8.015(19);
Sn(1)-O(21) 2.2281(16), Sn(1)-C(21) 2.094(2); Sn(1)-C(11)
2.062(2); O(12)-Sn(1)-O(11) 152.74(5); O(1)-Sn(1)-O(21)
177.91(6); O(11)-Sn(1)-O(1) 86.53(6); O(21)-Sn(1)-O(11)
91.49(6); C(11)-Sn(1)-C(21) 175.82(9).
δ(1H(CH2)) (4.60 ppm for 5, 5.30 ppm for 6) are shifted
downfield in comparison to 3 (4.12 ppm) and 4 (5.00 ppm) and
show further forcing of Sn-Y intramolecular interactions as
the result of an increase of Lewis acidity of the central tin atom
Figure 3. Polymeric structure of 6 mediated by hydrogen-bonding
interactions. Hydrogen atoms have been omitted for clarity.
Bu2Sn(OH2)4]2+[2,5-Me2C6H3-SO3-]2}(averageSn-Ow2.271(3)
Å),8a {[n-Bu2Sn(OH2)(Phen)(O3SC6H3-2,5-Me2)]+[2,5-Me2C6-
H3SO3]-} (Sn-Ow 2.273(3) Å), and in {[R2Sn(OH2)2-
(OPPh3)2]2+[CF3SO3-]2} (Sn-O ) 2.254(2)Å for R (n-Bu) and
2.237(3) Å for R(Me).8d The Sn1-O21 distance (involving the
OTf group) is 2.2281(16) Å and indicates that in the current
instance tin is bound more tightly to the OTf group than in
[n-Bu2Sn(µ-OH)-(OH2)(O3SCF3)]2 (Sn-O 2.622(4) Å).13
1
in the ionic compounds 5 and 6. The H NMR spectra also
revealed broad signals at 3.42 ppm (5) and 4.11 (6) proving
the coordination of water to the central tin atom. The 1H NMR
spectroscopy at various temperatures (range of 300-170 K)
revealed the presence of one set of sharp signals of CH2 and
CH3 protons, indicating that both CH2Y groups are coordinated
mutually in trans positions giving in 5 and 6. The IR spectra
proved the presence of both covalently bound and ionic OTf
groups in 5 and 6 as well as the presence of coordinated water
molecule (v(OH) at 3064 for 3 and at 3695 for 4).11 The positive
modes of the ESI/MS spectra of 5 and 6 showed the presence
of intensive peak at m/z ) 405 and 379 assigned to
[L1SnPh(OH)]+ and [L2SnPh(OH)]+, fragments of starting ionic
organotin(IV) cations [L1SnPh(OH2)OTf]+ and [L2SnPh(OH2)-
OTf]+.
The X-ray structure analysis of 6 proved these assumptions.
Compound 6 is formed by the diorganotin(IV) cation
[L2SnPh(OH2)OTf]+ compensated by OTf anion. The structure
of diorganotin(IV) cation [L2SnPh(OH2)OTf]+ shows the central
tin atom (Sn1) with an octahedral coordination environment
comprising two oxygen atoms (O11 and O12) of the L2 ligand,
two oxygen atoms from water (O1) and OTf group (O21), and
two carbon atoms from the L2 ligand C(21) and phenyl group
C(11) arranged in trans geometry with respect to each other
(Figure 2). The bond angles O(12)-Sn(1)-O(11) ) 152.74(5)°,
O(1)-Sn(1)-O(21) ) 177.91(6)°, and C(11)-Sn(1)-C(21) )
175.82(9)°, respectively, indicate the distortion from an ideal
octahedral geometry (Figure 2). All four oxygen atoms are
coordinated to the tin atom by a strong intramolecular interaction
Sn-O (the range of Sn-O is 2.2281(16)-2.2561(16) Å). The
Sn1-O1 distance (involving the coordinated water molecule)
is 2.2363(17) Å and is similar to that found in {[n-
The free OTf counteranion in 6 is involved in an O-H- - -O
hydrogen bonding with one of the coordinated water molecules
(H2- - -O33) (Figure 3) bringing thus two molecules of 6
together to form a centrosymmetric dimer as a result of the
hydrogen bonding (O-H- - -O) between the coordinated water
and the OTf counteranions. Two of the oxygen atoms (O33 and
O31) of each OTf anion and both the hydrogen atoms (H1 and
H2) of the water (O1) molecule are involved in this hydrogen-
bonding interaction to form a 12-membered hydrogen-bonded
ring (Figure 3). The bond parameters involved in this interaction
[O- - -O31 2.658(53) Å, O1-H- - -O31 174.24(47)°, O1- - -O33
2.655(5) Å, and O1-H2- - -O33 174.96(61)°] indicate that the
hydrogen bonds formed are quite strong (see Table 1, Supporting
Information). These parameters are comparable to those found
in {[n-Bu2Sn(OH2)4]2+[2,5-Me2C6H3-SO3-]2}8a and in {[n-
Bu2Sn(OH2)3-[µ-L]-n-Bu2Sn(OH2)3]2+[L]2-} (L ) 1,5-C6H10-
(SO3-)2).8b The remaining oxygen atom (O32) of free OTf
counteranion of 6 is involved in intermolecular C-H- - -O
hydrogen bonding between the dimmers to give polymeric tape
(Figure 3). The hydrogen atom involved in this interaction
belongs to the methylene group (H17) of L2 ligand. These
dimensional tapes are together connected by an additional
intermolecular C-H- - -F interaction involving the second
methylene group (H19) of L2 ligand and fluorine atom (F23)

3746 Organometallics, Vol. 27, No. 15, 2008
Kasˇna´ et al.
Scheme 1. Formation of Sn2 Dication [PhL2Sn-µ-(OH)2-SnL2-
of free OTf anion to afford a three-dimensional network (see
the Supporting Information).
Ph]2+ 2*(1-CB11H12)- (9), the Final Hydrolytic Product of 8
The use of carborane anion [1-CB11H12]- as a less nucleo-
philic polar group instead of OTf- group was another step that
should result to the preparation of more Lewis acidic tin centers.
The reaction of 1 and 2 with 1 equiv of AgCB11H12 in CH2Cl2
yielded to diorganotin(IV) cations {[L1SnPhCl]+ [1-CB11H12]-}
(7) and {[L2SnPhCl]+ [1-CB11H12]-} (8) (eq 3).
CH2Cl2
L1,2SnPhCl2 + Ag+[1-CB11H12]-
L1(1), L2(2)
8
[L1,2SnPhCl]+[1-CB11H12]- + AgCl (3)
L1(7), L2(8)
The values of δ(119Sn) in compounds 7 (-73.33 ppm) and 8
(-88.1 ppm) are shifted downfield compared with 1 (-212.8
ppm) and 2 (-208.8 ppm) and fall to the region typical for [3
+ 2] coordinated organotin cations.14,16 The 11B NMR spectra
of 7 and 8 showed three distinct signals in a 1:5:5 ratio that is
typical for noncoordinated CB11H12 anion.17 The 1H NMR
spectra of compounds 7 and 8 exhibit an AB system of CH2Y
groups indicating their diastereotopic character and two signals
of NMe2 groups in 7 proving the presence of prochiral central
tin atom in 7 and 8. The geometry of the diorganotin cation in
both compounds 7 and 8 can be thus described as the trans-
trigonal bipyramid with CH2Y groups in axial positions and
two carbon atoms (one involved in Ph group and second one in
L1 or L2 ligand) and chlorine atom in the equatorial plane. The
presence of two strong Sn-Y interactions is also corroborated
by a downfield shift of CH2Y units in 7 (4.03 ppm) and 8 (5.19
ppm) in comparison to the values found in 1 (3.96 ppm) and 2
(4.68 ppm). The positive part of the ESI/MS showed the most
intense peak at m/z ) 423 for 7 (m/z ) 397 for 8) assignable
to cations [L1SnPhCl]+ and [L2SnPhCl]+.
Compound 8 underwent facile hydrolysis resulting in Sn2
dication {[PhL2Sn-µ-(OH)2-SnL2Ph]2+ 2*(1-CB11H12)-} (9).18
Thus, the formation of compound 9 can be explained by the
coordination of water molecule to the tin atom of 8 in the first
step (similarly to 5 or 6). However, the use of low nucleophilic
1-CB11H12anion increases Lewis acidity of the tin(IV) center in 8
leading to the polarization of O-H bond in the coordinated water.
This polarization can lead to easy elimination of HCl followed by
the formation of the dimeric compound 10 (Scheme 1).
isolated and the Sn2 dication 9 was obtained as the final
hydrolytic product.
Experimental Section
General Methods. The starting compounds (L1,2)SnPhCl2 (1 and
2) were prepared according to the literature. The preparation,
characterization, and X-ray structure of Sn2 dication {[PhL2Sn-µ-
(OH)2-SnL2Ph]2+ 2 · (1-CB11H12)-} (9) was published previously,18
but a new procedure described here gives better yields. All reactions
were carried out under argon using standard Schlenk techniques.
Solvents were dried by standard methods and distilled prior to use,
1
and operations with silver salts were light protected. The H,11B,
13C, and119Sn NMR spectra were recorded on a Bruker AMX360
spectrometer at 300 K in CDCl3. Appropriate chemical shifts were
1
calibrated on: H-residual peak of CHCl3 (δ ) 7.27 ppm), 11B-
external BF3 · OEt2 (δ ) 0.00 ppm), 13C-residual peak of CHCl3
(δ ) 77.23 ppm), 119Sn-external tetramethylstannane (δ ) 0.00
ppm). Chemical shifts data are given in ppm and coupling constants
in hertz. Electrospray mass spectra (ESI/MS) were recorded in the
positive mode on an Esquire3000 ion trap analyzer (Bruker
Daltonics) (range 100-600 m/z) and in the negative mode on the
Platform quadrupole analyzer (range 100-800 m/z). The samples
were dissolved in acetonitrile and analyzed by direct infusion (flow
rate 1-10 µL/min). For the detection of negative ions of m/z <
60, a quadropole analyzer had to be used in place of the ion trap.
The IR spectra were recorded on a Perkin-Elmer 684 equipment.
Preparation of [{2,6-(Me2NCH2)2C6H3}SnPh(OTf)2] (3). L1Ph-
SnCl2 (0.69 g, 1.5 mmol) in CH2Cl2 (40 mL) was stirred with
AgOTf (0.8 g, 3 mmol) for 2 h. The AgCl was removed by filtration,
the filtrate evaporated, and the solid residue washed with pentane
(2 × 5 mL) to give 3 (yield 0.98 g, 95%). Mp: 253-255 °C. Anal.
Calcd for C20H24F6N2O6S2Sn (MW 685.23): C, 35.06; H, 3.53.
Found: C, 35.00; H, 3.50. MW ) 685. MS: m/z 149, 100% [OTf]-;
m/z 537, 100% [M - OTf]+. 1H NMR (CDCl3): δ (ppm); 2.68 (s,
12H, N(CH3)2); 4.12 (s, 4H, CH2); 7.29-7.99 (complex pattern,
8H, SnPh, SnC6H3). 13C NMR (CDCl3): δ (ppm) 47.29 (CH3); 62.42
(CH2, nJ(119Sn,13C) ) 68.9 Hz); 119.56 (q-CF3, nJ(19F,13C) )
316.85 Hz); SnC6H3: 129.10 (C(1)), 138.46, 127.10, 133.14; SnPh2:
134.31 (C′(1)), 135.69, 130.42, 132.59. 119Sn NMR (CDCl3): δ
(ppm) -320.10. IR (solution in CHCl3): (cm -1) νs (SO3) ) 1040s;
νas (SO3) ) 1264s, 1188s.
Conclusion
In conclusion, an important role of Y,C,Y-ligands in con-
trolled hydrolysis pathway was showed. The presence of Y,C,Y
ligands in diorganotin(IV) compounds resulted to stabilization
of highly Lewis acidic tin atoms in air and moisture sensitive
compounds 3 and 4. Their exposition to air led to the isolation
of the hydrated forms 5 and 6. Substitution of [OTf]- by
[1-CB11H12]- group resulted to the stabilization of diorgano-
tin(IV) cations 7 and 8. Thanks to the presence of highly Lewis
acidic tin center, however, the hydrated form of 8 could not be
Preparation of [{2,6-(MeOCH2)2C6H3}SnPh(OTf)2] (4). Simi-
lar procedure to that for 3. L2PhSnCl2 (0.86 g, 2 mmol) and AgOTf
(1 g, 4 mmol) resulted to 4 (yield 1.25 g, 95%). 4. Mp: 256-260
°C. Anal. Calcd for C18H18F6O8S2Sn (MW 659.15): C, 32.80; H,
2.75. Found: C, 32.70; H, 2.73. MW ) 659. MS: m/z 149, 100%
[OTf]-; m/z 511, 100% [M - OTf]+. 1H NMR (CDCl3): δ (ppm)
(16) (a) Bokii, N. G.; Zakharova, G. N.; Struchkov, Y. T. J. Struct.
Chem. 1970, 11, 828. (b) Amini, M. M.; Heeg, M. J.; Taylor, R. W.;
Zuckerman, J. J.; Ng, S. W. Main Group Met. Chem. 1993, 16, 415.
(17) (a) Kasˇna´, B.; Jambor, R.; Dosta´l, L.; Císarˇová, I.; Holecˇek, J.;
ˇ
St´ıbr, B. Organometallics 2006, 25, 5139. (b) Fox, M. A.; Mahon, M. F.;
Patmore, N. J.; Weller, A. S. Inorg. Chem. 2002, 41, 4567.
(18) Kasˇna´, B.; Dosta´l, L.; Císarˇová, I.; Jambor, R. Organometallics
2007, 26, 4080.
1
3.74 (s, 6H, CH3); 5.00 (s, 4H, CH2,nJ(119Sn, H) ) 10.38 Hz);

Hydrolysis of Diorganotin Compounds
Organometallics, Vol. 27, No. 15, 2008 3747
7.15 (d, 2H, H2′,6′); 7.45 (t, 1H, H4′); 7.58 (complex pattern, 4H,
H
Preparation of [{2,6-(MeOCH2)2C6H3}(Ph)Sn-µ-(OH)2-Sn-
(Ph){2,6-(MeOCH2)2C6H3}]+ 2 · [1-CB11H12]- (9). One microliter
of H2O was added to the THF solution of 8 (0.3 g, 0.4 mmol) at 0
°C, and the resulting suspension was stirred for 3 h. Insoluble
precipitate was filtered off, and the filtrate was evaporated to
dryness. The residue was washed with 15 mL of pentane to
precipitate a white solid characterized as 10. Yield: 0.2 g (75%).
Crystallography Studies. Colorless crystals were obtained by
layering n-hexane onto a dichloromethane solutions of the com-
pounds. Crystals of compounds of 3 and 6 were mounted on a glass
fiber with epoxy cement and measured on a KappaCCD four-circle
diffractometer with a CCD area detector by monochromatized Mo
K radiation () 0.71073 Å) at 150(2) K. The details pertaining to
the data collection and refinement for crystals are as follows. For
3: C20H24F6N2S2Sn, M ) 685.22, monoclinic, space group P21/c,
a ) 13.7458(3) Å, b ) 9.3395(10) Å, c ) 19.9533(4) Å, R ) 90°,
ꢀ ) 98.0965(9)°, γ ) 90°, Z ) 4, F ) 1.795 g · cm-3, µ ) 1.256
mm-1, crystal size 0.6 × 0.5 × 0.35 mm, crystal shape prism, θ
range 1-27.5°, Tmin,, Tmax 0.503, 0.653, 27364 reflections collected,
of which 5793 were independent [R(int) ) 0.0433], no. of observed
ref [I > 2σ(I)] 5464, no. of parameters 339, S all data 1.075, final
R indices [I > 2σ(I)]: R1 ) 0.0243, wR2 ) 0.0575.
3,5, H3‘,5‘); 8.03 (t, 1H, H4). 13C NMR (CDCl3): δ (ppm) 61.23
(CH3); 73.66 (CH2, nJ(119Sn, 13C) ) 46.5 Hz); 119.81 (q-CF3,
nJ(19F,13C) ) 318.3 Hz); SnC6H3: 128.75 (C(1),nJ(119Sn, 13C) )
348.64 Hz), 138.44, 124.08, 132.38; SnPh2: 134.33 (C′(1), nJ(119Sn,
13C) ) 405.69 Hz), 136.92, 131.05, 134.33. 119Sn NMR (CDCl3):
δ (ppm) -401.34. IR (solution in CHCl3): (cm -1) νs(SO3) )
1033 s; ν(SO3) ) 1258 s, 1177 s.
Preparation of [{2,6-(Me2NCH2)2C6H3}SnPh(OH2)(OTf)]+
[OTf]- (5). Compound 3 (0.5 g) was diluted in nondried CH2Cl2
(15 mL) after the solution was exposed to the air and slowly
evaporated to obtain an oily residue that was crystallized by addition
of hexane (10 mL). White crystalline material was identified as 5
(yield 0.4 g, 77%). Mp: 186-188 °C. Anal. Calcd for
C20H26F6N2O7S2Sn (MW 703.15): C, 34.16; H, 3.73. Found C,
34.00; H, 3.70. MW ) 703. MS: m/z 149, 100% [OTf]-; m/z 405,
100 [M - 2OTf - H]+. 1H NMR (CDCl3): δ (ppm) 3.06 (s, 12H,
N(CH3)2); 3.42 (bs, 2H, OH2); 4.61 (s, 4H, CH2); 7.51-7.94
(complex pattern, 8H, SnPh, SnC6H3). 13C NMR (CDCl3): δ (ppm)
43.59 (N(CH3)); 61.64 (s, CH2); 121.85 (q-CF3, nJ(19F,13C) ) 320.3
Hz); SnC6H3: not found (C(1)), 134.59, 131.04, not found; SnPh2:
not found (C′(1)), 133.72, 132.02, not found. 119Sn NMR (CDCl3):
δ (ppm) -303.58. IR (CHCl3 solution): (cm -1) νs(SO3) ) 1040s;
νas(SO3) ) 1169, 1259s, 1301s; ν(OH) ) 3064br.
For 6: C18H20F6O9S2Sn, M ) 677.15, triclinic, space group P-1,
a ) 10.0999(3) Å, b ) 10.4971(3) Å, c ) 11.9202(2) Å, R )
73.1794(16)°, ꢀ ) 86.1036(16)°, γ ) 85.1050(11)°, Z ) 2, F )
1.868 g · cm-3, µ ) 1.328 mm-1, crystal size 0.3 × 0.3 × 0.15
mm, crystal shape prism, θ range 1-27.5°, Tmin,, Tmax 0.786, 0.880,
18543 reflections collected, of which 5531 were independent [R(int)
) 0.0354], no. of observed ref [I > 2σ(I)] 5092, no. of parameters
336, S all data 1.040, final R indices [I > 2σ(I)]: R1 ) 0.0254,
wR2 ) 0.0601.
Preparation of [{2,6-(MeOCH2)2C6H3}SnPh(OH2)(OTf)]+
[OTf]- (6). Similar procedure to 5; 0.5 g of 4 was used to obtained
0.4 g of 6 (yield 75%). Mp: 191-192 °C. Anal. Calcd for
C18H20F6O9S2Sn (MW 677.16): C, 31.93; H, 2.98. Found: C, 31.90;
H, 2.94. MW ) 677. MS: m/z 149, 100% [OTf]-; m/z 379, 100%
1
[M - 2OTf - H]+. H NMR (CDCl3): δ (ppm) 3.43 (s, 6H, CH3);
4.10 (s, 2H, OH2); 4.99 (s, 4H, CH2); 7.44-7.62 (complex pattern,
8H, SnPh, SnC6H3). 13C NMR (CDCl3): δ (ppm) 59.67 (CH3); 73.42
(CH2, J(119Sn,13C) ) Hz); 121.77 (q-CF3, J(19F,13C) ) 320.3
Hz); SnC6H3: not found (C(1)), 144.75, 126.76, 132.55; SnPh2: not
found (C′(1)), 136.00, 130.71, 132.89. 119Sn NMR (CDCl3): δ
(ppm) -356.37. IR (solution in CHCl3): (cm -1) νs(SO3) ) 1032;
νas(SO3) ) 1171s, 1249s, 1277s; ν(OH) ) 3695 wm, 1625 s.
Preparation of [{2,6-(Me2NCH2)2C6H3}SnPhCl]+ [1-CB11H12]-
(7). Similar procedure to 3. L1SnPhCl2 (0.55 g, 1.2 mmol) and
AgCB11H12 (0.39 g, 1.2 mmol) resulted to 7 (yield 0.66 g, 97%).
Mp: 87-90 °C. Anal. Calcd for C19H36B11ClN2Sn (MW 565.59):
C, 40.35; H, 6.42. Found: C, 40.30; H, 6.40. MW ) 566. MS: m/z
423, 100 [M-CB11H12]+; m/z 143, 100 [CB11H12]-. 1H NMR
(CDCl3): δ (ppm) 2.41 (s, 6H, (CH3′)2); 2.47 (s, cage CH); 2.66 (s,
6H, N(CH3)2); 4.03 (AB, 4H, CH2, nJ(1H,1H) ) 15.0 Hz);
7.37-7.77 (complex pattern, 8H, SnPh, SnC6H3). 13C NMR
(CDCl3): δ (ppm) 46.76 (N(C′H3)); 47.14 (N(CH3)); 54.73 (s, cage
CH); 63.34 (s, CH2, nJ(119Sn,13C) ) Hz); SnC6H3: not found (C(1)),
141.47, 127.99, 134.83; SnPh: not found (C′(1)), 135.53, 131.22,
133.54. 119Sn NMR (CDCl3): δ (ppm) -73.33. 11B NMR (CDCl3):
δ (ppm) -14.90 (s, 1B, B(12)); -18.23 (s, 10B, B(7-11 and 2-6).
IR (suspension in Nujol): (cm -1) ν(BH) ) 2565.
n
n
The crystal structure of 10 was already published.18 The empirical
absorption corrections19 were applied (multiscan from symmetry-
related measurements). The structures were solved by the direct
method (SIR9720) and refined by a full-matrix least-squares
procedure based on F2 (SHELXL9721). Hydrogen atoms were fixed
into idealized positions (riding model) and assigned temperature
factors Hiso(H) ) 1.2Ueq(pivot atom); for the methyl moiety, a
multiple of 1.5 was chosen. The final difference maps displayed
no peaks of chemical significance. Crystallographic data for
structural analysis have been deposited with the Cambridge
Crystallographic Data Centre, CCDC no. 668524 and 668525 for
3 and 6, respectively. Copies of this information may be obtained
free of charge from the Director, CCDC, 12 Union Road,
Cambridge CB2 1EY, UK (fax: +44-1223-336033; e-mail:
deposit@ccdc.cam.ac.uk; internet: http://www.ccdc.cam.ac.uk).
Acknowledgment. We thank the Grant Agency of the
Czech Republic (project no.GA370468) and The Ministry
ofEducationoftheCzechRepublic(projectsno.VZ0021627501
and LC523) for financial support.
Preparation of [{2,6-(MeOCH2)2C6H3}SnPhCl]+ [1-CB11H12]-
(8). Similar procedure to 1. L2SnPhCl2 (0.432 g, 1.0 mmol) and
AgCB11H12 (0.33 g, 1.0 mmol) resulted in 8 (yield 0.52 g, 96%).
Mp: 145-148 °C. Anal. Calcd for C17H30B11ClO2Sn (MW 539.50):
C, 37.85; H, 5.60. Found: C, 37.81; H, 5.39. MW ) 540. MS: m/z
397, 100% [M - CB11H12]+; m/z 143, 100% [CB11H12]-. 1H NMR
(CDCl3): δ (ppm) 2.15 (s, cage CH); 3.86 (s, 6H, CH3); 5.19 (AB,
4H, CH2, nJ(1H,1H) ) 12.3 Hz); 7.43-7.87 (complex pattern, 8H,
SnPh, SnC6H3). 13C NMR (CDCl3): δ (ppm) 42.60 (s, cage CH);
61.10 (CH3), 74.0 (CH2, nJ(119Sn,13C) ) 36.10 Hz); SnC6H3: 131.73
(C(1)), 140.82, 125.08, 121.03; SnPh: 133.88 (C′(1)), 135.74,
131.31, 134.31. 119Sn NMR (CDCl3): δ (ppm) -88.13. 11B NMR
(CDCl3): δ (ppm) -10.03 (s, 1B, B(12)); -16.38 (s, 5B, B(7-11);
-20.37 (s, 5B, B(2-6)). IR (suspension in Nujol): (cm -1) ν(BH)
) 2569.
Supporting Information Available: Further details of the
structure determination of compounds 3 and 6, including atomic
coordinates, anisotropic displacement parameters and geometric
data. This material is available free of charge via the Internet at
http://pubs.acs.org.
OM8002015
(19) (a) SORTAV: Blessing, R. H. J. Appl. Crystallogr. 1997, 30, 421.
(b) PLATON: Spek, A. L. J. Appl. Crystallogr. 2003, 36, 7.
(20) Altomare, A.; Cascarano, G.; Giacovazzo, C.; Guagliardi, A.; Burla,
M. C.; Polidori, G.; Camalli, M. J. Appl. Crystallogr. 1994, 27, 435.
(21) Sheldrick, G. M. SHELXL97; University of Go¨ttingen: Go¨ttingen,
Germany, 1997.