Crystal structures and spectral studies of [Ph3Sn(O 2AsMe2)], [Bu2ClSn(O2AsMe 2)] and [PhClSn(O2AsMe2)(μ-OMe)]2

Article abstract of DOI:10.1002/zaac.200700415

[Ph₃Sn(O₂AsMe₂)] (1) and [PhClSn(O ₂AsMe₂)(μ-OMe)]₂ (3) have been synthesized by treatment of Ph₃SnCl and Ph₂SnCl₂ with Na(O₂AsMe₂) in methanol, respectively. [Bu ₂ClSn(O₂AsMe₂)] (2) has been prepared by the reaction of Bu₂SnCl₂ with HO₂AsMe₂ in methanol. X-ray diffraction studies show 1 to crystallize in the monoclinic space group P2₁/n with a = 699.8(1), b = 1961.4(2), c = 1433.6(2) pm, β = 95.17(1)°, and Z = 4. 2 also crystallizes monoclinic in the space group P2₁/m, the cell parameters being a = 480.6(1), b = 1992.7(2), c = 808.8(1) pm, β = 103.726(5)°, and Z = 2. Both compounds form infinite chains with alternating (Me₂AsO₂)^- and (R₃Sn)⁺ or (R₂ClSn)⁺ units. The dimer 3 consists of 8-membered (OSnOAs)₂ rings in which the tin atoms are bridged by methanolate bridges. It crystallizes triclinic in the space group P1 with a = 822.8(2), b = 910.4(2), c = 929.2(2) pm, α = 77.04(3)°, β = 82.35(3)°, γ = 68.69(3)°, and Z = 1 for the dimer. The vibrational and mass spectra of 1, 2 and 3 are given and discussed.

Full text of DOI:10.1002/zaac.200700415

DOI: 10.1002/zaac.200700415
Crystal Structures and Spectral Studies of [Ph3Sn(O2AsMe2)],
[Bu2ClSn(O2AsMe2)] and [PhClSn(O2AsMe2)(µ-OMe)]2
Abdel-Fattah Shihadaa and Frank Wellerb,*
a Zarqa/Jordan, Department of Chemistry, Faculty of Science, Hashemite University
b Marburg, Fachbereich Chemie der Philipps-Universität
Received August 7th, 2007.
Abstract. [Ph3Sn(O2AsMe2)] (1) and [PhClSn(O2AsMe2)(µ-OMe)]2
(3) have been synthesized by treatment of Ph3SnCl and Ph2SnCl2
with Na(O2AsMe2) in methanol, respectively. [Bu2ClSn(O2AsMe2)]
(2) has been prepared by the reaction of Bu2SnCl2 with HO2AsMe2
in methanol. X-ray diffraction studies show 1 to crystallize in the
monoclinic space group P21/n with a ϭ 699.8(1), b ϭ 1961.4(2),
c ϭ 1433.6(2) pm, β ϭ 95.17(1)°, and Z ϭ 4. 2 also crystallizes
monoclinic in the space group P21/m, the cell parameters being a ϭ
480.6(1), b ϭ 1992.7(2), c ϭ 808.8(1) pm, β ϭ 103.726(5)°, and
Z ϭ 2. Both compounds form infinite chains with alternating
(Me2AsO2)Ϫ and (R3Sn)ϩ or (R2ClSn)ϩ units. The dimer 3 consists
of 8-membered (OSnOAs)2 rings in which the tin atoms are bridged
by methanolate bridges. It crystallizes triclinic in the space group
¯
P1 with a ϭ 822.8(2), b ϭ 910.4(2), c ϭ 929.2(2) pm, α ϭ 77.04(3)°,
β ϭ 82.35(3)°, γ ϭ 68.69(3)°, and Z ϭ 1 for the dimer. The
vibrational and mass spectra of 1, 2 and 3 are given and discussed.
Keywords: Tin; Crystal structures; Vibrational spectra; Mass spec-
tra; Dimethylarsinates; Methoxo bridges
1 Introduction
In the latter dimer two tin atoms are connected by two
(O2PPh2) bridges in a bidentate fashion and by two bridged
methoxo groups leading to eight-memberd (SnOPO)2 and
four-membered Sn2O2 rings [9]. In the light of our earlier
experience with synthesis and structural studies of or-
ganotin diorganophosphinates [9], we made attempts to
prepare crystals of organotin dimethylarsinates suitable for
X-ray crystallographic studies.
The present work deals with the synthesis and crystal
structures of [Ph3Sn(O2AsMe2)] (1), [Bu2ClSn(O2AsMe2)]
(2), and [PhClSn(O2AsMe2)(µ-OMe)]2 (3). The vibrational
and mass spectra are given and discussed.
Various methods have been applied to the synthesis of
organotin diorganoarsinates. [Me2Sn(O2AsMe2)2] has been
prepared by the reaction of Me2SnCl2 with Ag(O2AsMe2)
[1] or with [Me4N](O2AsMe2)·H2O [2] in 1:2 molar pro-
portions. The oxidation of [RnSn(AsRЈ2)4Ϫn] (R, RЈ ϭ
alkyl, phenyl) by oxygen leads to [RnSn(O2AsRЈ2)4Ϫn
]
[3Ϫ5]. The reaction of Ph2SnCl2 with HO2AsPh2 in the
presence of triethylamine afforded [Ph2Sn(O2AsPh2)2] [4].
Treatment of R2SnCl2 (R2 ϭ Me2, Et2) with HO2AsMe2
in methanol at ambient temperature produced
[R2ClSn(O2AsMe2)] [6]. Despite the synthesis of several or-
ganotin diorganoarsinates, only the crystal structures of
[R2ClSn(O2AsMe2)] have been reported.
2 Results and Discussion
X-ray diffraction studies of [Me2ClSn(O2AsMe2)] and
[Et2ClSn(O2AsMe2)] show that the (O2AsMe2)Ϫ groups be-
have as bidentate bridge ligands between (R2ClSn)ϩ units
forming polymeric chain structures [6]. A similar chain
structure with (O2PMe2)Ϫ bridges was also found in the
analogous [Et2ClSn(O2PMe2)] [7]. In view of their possible
application as biocides and catalysts, numerous related or-
ganotin diorganophosphinates RnSn(O2PRЈ2)4Ϫn were syn-
thesized and structurally characterized by X-ray crystallo-
graphic studies [8, 9].
Crystals of [Ph3Sn(O2AsMe2)] (1) have been isolated from
the reaction of Ph3SnCl with an equimolar amount of
Na(O2AsMe2) in methanol at ambient temperature. The re-
action of Bu2SnCl2 with HO2AsMe2 under similar con-
ditions afforded [Bu2ClSn(O2AsMe2)] (2) along with HCl.
Crystalline [PhClSn(O2AsMe2)(µ-OMe)]2 (3) was formed
by treatment of Ph2SnCl2 with Na(O2AsMe2) (1:1) in meth-
anol according to the following equation.
2 Ph2SnCl2 ϩ 2 Na(O2AsMe2) ϩ 2 HOMe Ǟ
The reaction of Ph2SnCl2 with HO2PPh2 in methanol
gave [Ph2Sn(O2PPh2)2] along with [PhClSn(O2PPh2)OMe]2.
[PhClSn(O2AsMe2)(µ-OMe)]2 (3) ϩ 2 HPh ϩ 2 NaCl
The cleavage of an Sn-Ph bond in this reaction was
also observed in the synthesis of the analogous
[PhClSn(O2PPh2)(µ-OMe)]2 from Ph2SnCl2 and HO2PPh2
in methanol [9]. In this connection, it is worth noting that
the reaction of Ph3PbCl with HO2PR2 (R2 ϭ Me2, Ph2)
causes break of Pb-Ph and Pb-Cl bonds to give
* Dr. Frank Weller
Fachbereich Chemie der Universität
D-35032 Marburg
Fax: 004964212825653
E-Mail: weller@chemie.uni-marburg.de
Z. Anorg. Allg. Chem. 2008, 634, 339Ϫ344
 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
339

A.-F. Shihada, F. Weller
Table 1 IR and Raman Spectra (1200Ϫ400 cmϪ1 IR; 1200Ϫ100 cmϪ1 Raman) of 1, 2 and 3
[Ph3Sn(O2AsMe2)] (1)
[Bu2ClSn(O2AsMe2)] (2)
[PhClSn(O2AsMe2)(µ-OMe)]2 (3)
IR
Raman
IR
Raman
IR
Raman
Assignment
1195 vw
1186 vw
1155 vw
1082 vw
1070 vw
1194 w
1195 vw
1183 vw
1148 vw
1185 w
1156 w
1157 m
1078 m
1158 m
1083 vw
δ(CH)Ph in-plane
·
1088 w
1068 w-m
1073 w
1076 w
1065 w
1027 m
1049 m
1024 w
1027 m
δ(CH)Ph in-plane
ν(C-C)Bu
1018 w
1012 s
ν(O-CH3)
ν(C-C)Bu
1005 vw
997 w
1001 vs
987 vw
1001 vs
990 vw
976 vw
Ph ring breathing
916 m
917 vw
907 w
890 w
ρ(CH3)
·
886 vw
875 vw
865 m-s
877 s
886 m
855 vw
838 vw
869 vs
798 vs
744 vw
843 m
815 vs
838 w
νas(AsO2)
836 vs
797 s
823 vw
800 vw
νs(AsO2)
ρ(CH2)
750 vw
732 s
700 s
742 vw
702 vw
735 m-s
698 m
δ(CH)-Ph out-of-plane
·
686 s
663 w
655 vs
637 w
620 m
604 w
662 vs
653 s
δ(C-C) out-of-plane
νas(AsC2)
658 vw
634 w
650 m
652 w
651 w
620 m-s
615 vs
(C-C-C) Ph bend
νs(AsC2)
νs(SnC2)
608 w
602 m
611 vs
603 s
611 vw
493 vw
462 s
452 s
ν(Sn-O-Sn)
468 vw
464 m
453 m
441 w
453 s
454 w
νs(Sn-OAs)
444 vw
405 w
439 vw
398 vw
372 vw
351 w
396 vw
366 m-s
324 vw
296 m
ν(SnCl)
νas(SnPh3)
286 vw
271 vw
268 m
257 m
237 vw
246 m
228 vs
233 vw
ν(SnCl)
220 w
188 s
ν(SnPh) in-phase
νs(SnPh3)
211 s
196 vw
179 w
169 w
156 w
[Ph2Pb(O2PR2)2] [10]. Moreover, [Ph3Sn(O2AsMe2)] (1) was
obtained as a colorless insoluble powder by the oxidation
of [Ph3SnAsMe2] with oxygen [5]. [Bu2ClSn(O2AsMe2)] was
prepared as white precipitate from [Me4N][O2AsMe2]·H2O
and Bu2SnCl2 (1:1) in ethanol [2].
dentately bonded (O2AsMe2)Ϫ [2, 6]. The medium band at
602 cmϪ1 (IR) and the strong band at 603 cmϪ1 (Raman)
in the spectra of 2 are assigned to νs(SnC2). The appearance
of this frequency in both IR and Raman spectra is consis-
tent with the nonlinear SnC2 arrangement. The absence of
these bands in the spectra of 1 and 3 supports this assign-
ment. A corresponding νs(SnC2) mode appears as strong
band at 603 cmϪ1 only in the Raman spectrum of
[Bu2Sn(O2PPh2)2] in which tin atoms are hexa-coordinated
with the butyl groups in trans positions [9, 12]. The
νas(SnC2) vibration of 2 is not observed and may be obscure
by the νas(AsC2) bands. The Raman spectra of 1 and 3
exhibit the characteristic bands due to phenyl ring breath-
ing at 1001 cmϪ1 and the typical (C-C-C) bending-in-plane
Vibrational Spectra
The observed IR and Raman frequencies of 1, 2 and 3
(Table 1) are assigned by comparison with the vibrational
spectra of [R2ClSn(O2AsMe2)] [6], with the Raman spec-
trum of [PhClSn(O2PPh2)(µ-OMe)]2 [9] and with vi-
brational spectra of related compounds [2, 5, 7, 11]. The IR
and Raman spectra of 1, 2 and 3 show νas (AsO2) and
νs(AsO2) bands between 790-900 cmϪ1 which indicate bi-
vibrations at 620 cmϪ1
.
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[Ph3Sn(O2AsMe2)], [Bu2ClSn(O2AsMe2)] and [PhClSn(O2AsMe2)(µ-OMe)]2
Table 2 Characteristic ions formed in the 70 eV mass spectra of 1, 2 and 3 (m/e (%))
[Ph3Sn(O2AsMe2)] (1)
R ؍ Ph
[Bu2ClSn(O2AsMe2)] (2)
[PhClSn(O2AsMe2)(µ-OMe)]2 (3)
R ؍ Ph
R ؍ Bu
699 (6)
585 (3)
RCl2Sn2(O2AsMe2)2(OMe)ϩ2
R3Sn2O5As2Meϩ4
RCl2Sn2(O2AsMe2)ϩ2
Cl2Sn2(O2AsMe2)2OMeϩ
RSn2O5As2Meϩ4
Cl2Sn2(O2AsMe2)O2AsMeϩ
RCl2HSn2O2AsMe2
RSn(O2AsMe)ϩ2
Sn(O2AsMe2)2OMeϩ
R2SnO2AsMeϩ2
R2ClSnO2AsMeϩ
RClSn(O2AsMe2)ϩ
R3Snϩ
721 (3)
659 (2)
613 (3)
567 (3)
503 (2)
451 (1)
471 (4)
425 (2)
411 (100)
351 (2)
391 (5)
349 (7)
291 (3)
269 (27)
247 (43)
257 (13)
212 (48)
369 (2)
351 (4)
309 (76)
267 (12)
257 (3)
232 (19)
R2ClSnϩ
RCl2Snϩ
Sn(O2AsMe2)ϩ
RClSnϩ
257 (26)
RMe2Snϩ
227 (10)
197 (10)
RSnϩ
177 (5)
190 (7)
155 (48)
197 (17)
SnClϩ2
SnClϩ
Rϩ2
154 (6)
154 (100)
137 (6)
HO2AsMeϩ2
138 (4)
O2AsMeϩ2
MeSnϩ
135 (1)
120 (5)
SnHϩ
121 (14)
Snϩ
120 (10)
107 (54)
91 (10)
77 (65)
AsOϩ2 , HOAsMeϩ
AsOϩ, HAsMeϩ
Rϩ
91 (8)
77 (11)
91 (4)
57 (100)
The band at 493 cmϪ1 in the Raman spectrum of 3 is
attributed to νs(Sn-O-Sn). The region of 480-530 cmϪ1 is
given for ν(Sn-O-Sn) modes in dimeric compounds contain-
ing bridging alkoxy groups [13]. The Sn-Ph vibrations in
phenyltin compounds fall within the 200-300 cmϪ1 range
[14]. Consequently, the bands at 286 cmϪ1 and at 211 cmϪ1
in the Raman spectrum of 1 are assigned to νas(SnPh3) and
νs(SnPh3), respectively, and the band at 220 cmϪ1 in the
Raman spectrum of 3 is ascribed to the ν(Sn-Ph) in-phase
vibration. The ν(SnCl) vibrations in the Raman spectra of
2 and 3 are assigned by comparison with ν(SnCl) in the
spectra of [R2ClSn(O2AsMe2)], [PhClSn(O2PPh2)(µ-OMe)]2,
and with consideration of the Sn-Cl bond length from X-ray
data [6, 9]. Accordingly, the band at 228 cmϪ1 and 296 cmϪ1
are attributed to ν(SnCl) in 2 and 3, respectively.
tively high abundance compared with R3Snϩ and RSnϩ
suggesting the greater ease with which Sn-C bonds are
cleaved compared with Sn-Cl bonds. In harmony herewith
molecular ions minus chlorine are not observed in the spec-
tra of 2 and 3. The peaks at 227 and 135 in the mass spec-
trum of 1 are assigned to the ions PhMe2Snϩ and MeSnϩ,
respectively. The appearance of such peaks can be con-
sidered as an indication for methyl groups transfer.
The mass spectra of 1, 2, 3, and [Et2ClSn(O2AsMe2)] [6]
display peaks due to the ion Sn(O2AsMe2)ϩ. On the
other hand, the mass spectra of many organotin
diorganophosphinates such as [Et2ClSn(O2PMe2)] [7] and
[Bu2Sn(O2PR2)2] (R ϭ Me, Ph) [12] exhibit the analogous
Sn(O2PR2)ϩ ions as base peaks. The spectrum of 2 shows
BuCl2HSn2O2AsMeϩ2 and SnHϩ ions which may be formed
by β-hydrogen elimination.
Mass Spectra
Table 2 gives the principal peaks in the EI mass spectra
(70 eV) of the compounds 1, 2, and 3.
Structural results
Compounds of type [R3Sn(O2ERЈ2)] have been investigated
structurally for E ϭ phosphorus [15Ϫ19], whereas for arsen
only an analogous hydrogen arsenate is reported, composed
of [R3SnO2AsOOH]2Ϫ units [20]. Apparently the array of
the O-Sn-O-E chain links depends largely on the volume of
the substituents at atom E. With big ligands the chains tend
to close to ring systems of various sizes [15Ϫ17], which also
holds for polymers in which Ph3Sn groups are linked by
transition metalates [21]. They can also evade sterical stress
coiling to helices [19], and when the the substituents RЈ are
methyl groups, too, a helix results [20]. The arsinate 1, in
The molecular ion of the monomer is absent but the mass
spectrum of 1 exhibits the molecular ion minus phenyl rad-
ical (Ph2SnO2AsMeϩ2 ) as a base peak. Related triphenyltin
diorganophosphinates similarly show (Ph2SnO2PRϩ2 ) (R ϭ
Me, Ph) as base peaks [11]. The molecular ion of 2 minus
butyl group and that of 3 minus phenyl group appear also
in the spectra of 2 and 3 respectively. However Buϩ and
Phϩ2 represent the base peaks of 2 and 3, respectively. The
mass spectra of 2 and 3 show chlorine containing fragments
RCl2Snϩ, R2ClSnϩ and RClSnϩ (R ϭ Bu or Ph) with rela-
Z. Anorg. Allg. Chem. 2008, 339Ϫ344
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341

A.-F. Shihada, F. Weller
which longer As-O distances give additional space, forms
infinite chains of almost collinear O-Sn-O units, with a
bond angle of 178°, linked by O-As-O bridges with angles
of 106°, all pointing in the same direction (Fig.1). The
phenyl groups at the tin atom do not allow for an
alternating orientation of the AsO2 bridges as found in
[Me3Sn(O2PMe2)] for the PO2 motifs [20]. This chain con-
figuration forces phenyl group 3 (C31 to C36) into a posi-
tion nearly coplanar with the equatorial plane at the tin
atom (the angle of the two planes is 3.5°) Ϫ the other phe-
nyl groups are set at 85.9° (C21 to C26) and 66.4° (C21 to
C26) to the plane SnC3. Bond lengths and angles are depen-
dent on structural tension in the chains. In the phosphi-
nates Sn-O bond lengths as well as O-P-O angles decrease
slightly from the four-membered rings [15, 16] (224-227 pm,
117°) to the six-membered ring and the open chains [17, 19]
(220-221 pm, 115-117°) with decreasing chain stress. In 1
both values are found very low (Tab.3), indicating an essen-
tially unstressed system.
teractions are formed, whereas in the diethyltin compound
the structure is governed by intramolecular forces, leading
to strongly folded chains [6]. Chlorodibutyltindimethylar-
sinate (2) is isostructural to the diethyl compound Ϫ it crys-
tallizes in the space group P21/m with the polymer chain
lying in the mirror plane and running along the x-direction
(Fig. 2). Same as in [Et2ClSn(O2AsMe2)] an extremely short
Sn-O bond (Sn-O(2), 203 pm) is found for one oxygen
atom, caused by a trans interaction with the loose contact
of the tin atom with O(2)Ј of the next asymmetric unit
(SnϪO(2)Ј 307 pm) (Table 4). Alternating [O-SnϪO-SnϪ]
motifs like this are well known from analogous carboxylates
[22, 23], where the Sn-O distances are more equalized.
The bond Sn-Cl (259 pm) is slightly shorter than in
[Et2ClSn(O2AsMe2)], (Sn-Cl 262 pm) [6], which correlates
with the weaker interaction SnϪO(2)Ј (307 pm compared
with 304 pm in the diethyl compound).
Replacement of one organic substituent R in the formula
[R3Sn(O2ERЈ2)] by a chloro ligand gives a class of com-
pounds, some structures of which are already known for
EϭP and As [6, 7]. With methyl groups at at the tin and
arsen atoms parallel chains with strong intermolecular in-
Fig. 1 Perspective view [27] of a section of the chains in 1. Atom
numbering is given for the asymmetric unit and for some adjacent
atoms (probability level 50 %).
Fig. 2 ORTEP view [27] of two asymmetric units of 2 and the
equivalents generated by the mirror plane (thermal ellipsoids drawn
at 50 % level).
Table 3 Bond lengths/pm and angles/° for [Ph3Sn(O2AsMe2)] (1)
Table
4 Bond lengths/pm and angles/° for [(n-Bu)2ClSn-
(O2AsMe2)] (2)
Sn-C(11)
Sn-C(21)
Sn-C(31)
Sn-O(1)
Sn-O(2)Ј
As-O(1)
As-O(2)
As-C(4)
As-C(5)
215.2(2)
216.6(2)
215.2(2)
216.5(4)
217.1(4)
167.3(4)
166.0(4)
188.0(5)
192.1(6)
C(11)-Sn-C(21)
C(11)-Sn-C(31)
C(21)-Sn-C(31)
C(11)-Sn-O(1)
C(11)-Sn-O(2)Ј
C(21)-Sn-O(1)
C(21)-Sn-O(2)Ј
C(31)-Sn-O(1)
C(31)-Sn-O(2)Ј
O(1)-Sn-O(2)Ј
O(1)-As-O(2)
O(1)-As-C(4)
O(1)-As-C(5)
O(2)-As-C(4)
O(2)-As-C(5)
C(4)-As-C(5)
As-O(1)-Sn
122.4(1)
118.3(1)
119.3(1)
89.1(2)
Sn-O(1)Ј
Sn-O(2)
218.2(2)
O(1)Ј-Sn-O(2)
O(1)Ј-Sn-C(11)
O(1)Ј-Sn-Cl
O(2)-Sn-C(11)
O(2)-Sn-Cl
C(11)-Sn-C(11)Љ
C(11)-Sn-Cl
Sn-O(1)Ј-AsЈ
Sn-O(2)-As
Sn-C(11)-C(12)
C(11)-C(12)-C(13)
C(12)-C(13)-C(14)
O(1)-As-O(2)
O(1)-As-C(3)
O(2)-As-C(3)
C(3)-As-C(3)Љ
82.93(8)
94.80(6)
164.72(6)
110.93(6)
81.78(6)
137.9(1)
90.66(6)
117.8(1)
136.9(1)
115.8(1)
112.0(2)
112.8(2)
102.0(1)
111.21(8)
110.28(8)
111.5(1)
203.1(2)
306.7(2)
213.3(2)
258.77(7)
168.4(2)
170.2(2)
190.3(2)
152.4(3)
152.4(3)
152.7(4)
89.2(2)
Snٞ-O(2)
Sn-C(11)
Sn-Cl
91.6(1)
88.9(1)
91.1(1)
As-O(1)
90.1(2)
As-O(2)
178.3(2)
106.4(2)
110.7(2)
109.5(3)
112.0(2)
109.0(3)
109.2(3)
141.0(2)
143.6(2)
As-C(3)
C(12)-C(13)
C(11)-C(12)
C(13)-C(14)
AsЈ-O(2)Ј-Sn
Symmetry transformations used to generate equivalent atoms (see figure 1):
ElЈ Ϫ1ϩx, y, z
Symmetry transformations used to generate equivalent atoms:
ElЈ xϪ1, y, zElЉ x, 1.5Ϫy, z
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[Ph3Sn(O2AsMe2)], [Bu2ClSn(O2AsMe2)] and [PhClSn(O2AsMe2)(µ-OMe)]2
Cleaving off one substituent
R
from the unit
Table 5 Bond lengths/pm and angles/° for [PhClSn(O2AsMe2)(µ-
OMe)]2 (3)
[R2ClSn(O2AsMe2)] (e.g. for R ϭ Ph, leaving as benzene)
gives a chain closing to a centrosymmetric dimer of the for-
mula [RClSn(O2AsRЈ2)(µ-OMe)]2 (3) with (Sn-O-As-O)2 8-
membered rings, in which the charge defect at the tin atom
is made up for by methanolate bridges (Fig. 3) as found for
the corresponding phosporus compound [9]. They originate
from the solvent methanol which provides the proton for
the leaving hydrocarbon. Tin and oxygen atoms are co-
planar with a maximal deviation of 16 pm of the best plane
from which the arsen atoms have a distance of 56 pm. The
coordination polyhedron of the tin atom is a distorted octa-
hedron in which by the asymmetry of the methanolate
bridges one of the Sn-O bond lengths is 217 pm compared
with 210 pm of the others and accounts for the relatively
short Sn-Cl bond (242 pm) (cf. 2) in trans position. Like
in the analogous phosphinate the bridging O atom has a
pyramidal configuration with a sum of the bond angles of
348° (bond lengths and angles are summarized in
Table 5).
Sn-O(1)
Sn-O(2)Ј
Sn-O(3)
Sn-O(3)Ј
Sn-C(1)
Sn-Cl
As-O(1)
As-O(2)
As-C(7)
As-C(8)
O(3)-C(9)
210.4(4)
209.5(4)
210.7(4)
217.4(5)
214.8(3)
242.1(2)
168.3(5)
169.7(4)
190.0(8)
190.0(7)
146.6(9)
O(1)-Sn-O(2)Ј
O(1)-Sn-O(3)
O(1)-Sn-O(3)Ј
O(2)Ј-Sn-O(3)
O(2)Ј-Sn-O(3)Ј
O(3)-Sn-O(3)Ј
O(1)-Sn-C(1)
O(2)Ј-Sn-C(1)
O(3)-Sn-C(1)
O(3)Ј-Sn-C(1)
O(1)-Sn-Cl
163.7(2)
82.1(2)
85.3(2)
83.7(2)
83.3(2)
74.5(2)
95.7(2)
96.8(2)
169.2(2)
94.8(2)
94.0(2)
94.1(2)
91.1(1)
165.6(1)
99.6(2)
113.3(2)
110.8(3)
106.2(3)
110.4(3)
106.2(3)
109.7(3)
122.5(4)
120.1(4)
105.5(2)
124.4(3)
125.1(2)
O(2)Ј-Sn-Cl
O(3)-Sn-Cl
O(3)Ј-Sn-Cl
C(1)-Sn-Cl
O(1)-As-O(2)
O(1)-As-C(7)
O(1)-As-C(8)
O(2)-As-C(7)
O(2)-As-C(8)
C(7)-As-C(8)
C(9)-O(3)-Sn
C(9)-O(3)-SnЈ
Sn-O(3)-SnЈ
As-O(2)-SnЈ
As-O(1)-Sn
Symmetry transformation used to generate equivalent atoms:
ElЈ 1Ϫx, 1Ϫy, 1Ϫz
Synthesis of [Ph3Sn(O2AsMe2)] (1)
A solution of 0.11 g Na(O2AsMe2) (0.70 mmol) in 5 mL methanol
was added to 0.27 g (0.70 mmol) Ph3SnCl in 15 mL methanol.
After one week a precipitate was formed, which was filtered off
and the mother liquor was set aside in an open flask. After one
week crystals of [Ph3Sn(O2AsMe2)] (1) (10 mg) were formed and
filtered off.
Synthesis of [Bu2ClSn(O2AsMe2)] (2)
A solution of 0.5 g (3.6 mmol) HO2AsMe2 in 10 mL methanol
was added to 0.6 g (2.0 mmol) Bu2SnCl2 in 15 mL methanol. After
two weeks a very small quantity of crystalline substance was
formed, which was filtered off. The filtrate was set aside in an
open flask at ambient temperature. After two days crystals of
[Bu2ClSn(O2AsMe2)] (2) were formed and filtered off (250 mg).
Synthesis of [PhClSn(O2AsMe2)(µ-OMe)]2 (3)
A solution of 0.26 g (1.6 mmol) of NaO2AsMe2 in 10 mL methanol
was added to 0.56 g (1.6 mmol) of Ph2SnCl2 in 20 mL methanol.
Directly after the addition a precipitate was formed. After one
week the precipitate was filtered off and the mother liquor was set
aside in an open flask at ambient temperature.
Fig. 3 Perspective view of a dimer of 3 [27]. Atoms of the asym-
metric unit are numbered along with some relevant equivalent
atoms (all atoms drawn as 50 % probability ellipsoids).
After nine days small crystals of [PhClSn(O2AsMe2)(µ-OMe)]2 (3)
(40 mg) were formed and filtered off.
3 Experimental Section
The chemical reagents employed were obtained from commercial
sources and were used without further purification. Na(O2AsMe2)
was formed by treating HO2AsMe2 with an equimolar amount of
sodium methoxide in methanol and used as methanol solution.
X-ray structural investigations
Single crystals selected from the reaction products described above
were handled in oil, mounted on glass threads and measured at
Ϫ80 °C on Stoe diffractometers IPDS I (1 and 3) and IPDS II
(2). Crystal data, experimental details and details about structure
solution and refinement are comprehended in table 6. After data
reduction [24] the reflections were subjected to absorption correc-
tion (numerical (2) and with equivalent reflections (1, 3)). The
structures were solved with direct methods (1, 2) [25] and with the
aid of Patterson syntheses (3) [25], and the models were refined by
Infrared spectra were measured using KBr pellets on a Bruker in-
strument IFS 88. The Raman spectra were recorded using a Jobin
Yvon Labram HR 800 instrument with 632.8 nm helium neon
Laser excitation.
Mass spectra were measured on Varian MAT CH 7A (EI 70 eV)
(1) and on Finnigan MAT S (2, 3).
Z. Anorg. Allg. Chem. 2008, 339Ϫ344
 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.zaac.wiley-vch.de
343

A.-F. Shihada, F. Weller
Table 6 Crystal data, measurement, and structure refinement details for 1, 2, and 3
1
2
3
Formula
[Ph3Sn(O2AsMe2)]
486.98
monoclinic
P21/n
699.8(1)
1961.4(2)
1433.6(2)
[(n-Bu)2ClSn(O2AsMe2)]
405.32
[PhClSn(O2AsMe2)(µ-OMe)]2
Formula weight
Crystal system
Space group
a / pm
399.26
monoclinic
P21/m
triclinic
¯
P1
480.6(1)
822.8(2)
b / pm
1992.7(2)
910.4(2)
c / pm
808.8(1)
929.2(2)
α /deg
77.04(3)
ß / deg
95.174(13)
103.726(5)
82.35(3)
γ / deg
68.69(3)
V / pm3 x 10Ϫ4
Cell determination
ρcalc / g x cmϪ3
Z
1959.7(4)
752.4(1)
10047
1.789
2
400
40.41
IPDS II (Stoe)
71.073
192(2)
omega-scans
Ϫ6 Յ h Յ 6, Ϫ27 Յ kՅ 27,
Ϫ11 Յ l Յ10
2.04 to 29.28°
11619
2089 [R(int)ϭ0.0336]
2089
1849 [I>2sigme(I)]
face-indexed
630.9(3)
7166 (Θ 2.0 to 25.8)
2775 (Θ 2.2 to 25.7)
1.651
2.102
2
384
48.24
IPDS I (Stoe)
71.073
193(2)
phi scans
4
F(000)
960
µ (MoKα ) / cmϪ1
Diffractometer type
Wavelength / pm
T / K
29.88 cmϪ1
IPDS I (Stoe)
71.073
193(2)
phi scans
Ϫ8 Յ h Յ 8, Ϫ23 Յ kՅ 24,
Ϫ17 Յ l Յ17
1.76 to 25.99
15312
3809 [R(int)ϭ0.1115)]
3809
Scan mode
hkl range
Ϫ10 Յ h Յ 10, Ϫ11 Յ kՅ 11,
Ϫ11 Յ l Յ10
2.25 to 26.05°
6289
2309 [R(int)ϭ0.0817]
2309
Theta range for data collection
Reflections collected
Independent reflections
Reflections used for refinement
Observed reflections
Absorption correction
Programs used
Solution
Refinement
refined parameters
wR2 [all reflections]
R1 [I>2sigma(I)]
2223 [I>2sigma(I)]
based on equivalent reflections
1398 [I>2sigme(I)]
based on equivalent reflections
XCAD4[24], SHELXS-97, SHELXL-97[25], PLATON[26], SHELXTL[27],
Direct Methods/difmap
Direct Methods/difmap
Patterson Methods/difmap
Full-matrix least-squares on F2
188
90
131
0.0597
0.0343
0.002
0.0444
0.0211
0.018
0.0626
0.0363
(shift/error)max
ρfin (max/min) / eA
-0.002
Ϫ1
˚
0.638/Ϫ0.525
0.385/Ϫ1.025
0.731/Ϫ0.799
successive refinement cycles and difference Fourier syntheses [25].
Hydrogen atoms were introduced into the models as part of rigid
groups. Geometrical calculations were carried out by PLATON
[26].
[12] A.-F. Shihada, Z. Naturforsch. 1995, 50b, 745.
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Crystallographic data (excluding structure Factors) have been de-
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344
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Z. Anorg. Allg. Chem. 2008, 339Ϫ344