Synthesis of monomeric divalent Tin(II) compounds with terminal chloride, amide, and triflate substituents

Article abstract of DOI:10.1002/ejic.201000803

Monomeric three-coordinate (amidinato)tin chloride [PhC(NtBu) ₂SnCl] (1) was prepared by the reaction of N,Na′-di-tert- butylcarbodiimide, phenyllithium and SnCl₂. Themetathesis reaction of 1 with AgSO₃CF₃ and (

Full text of DOI:10.1002/ejic.201000803

FULL PAPER
DOI: 10.1002/ejic.201000803
Synthesis of Monomeric Divalent Tin(II) Compounds with Terminal Chloride,
Amide, and Triflate Substituents
Sakya S. Sen,[a] Malte P. Kritzler-Kosch,[a] Selvarajan Nagendran,[a] Herbert W. Roesky,*[a]
Tobias Beck,[a] Aritra Pal,[a] and Regine Herbst-Irmer[a]
Dedicated to Professor George B. Kauffman on the occasion of his 80th birthday
Keywords: Tin / N ligands / NMR spectroscopy / X-ray diffraction
Monomeric three-coordinate (amidinato)tin chloride [PhC-
(NtBu)2SnCl] (1) was prepared by the reaction of N,NЈ-
di-tert-butylcarbodiimide, phenyllithium and SnCl2. The
tion of 1 with L-selectride resulted in the formation of the
four-coordinate homoleptic tin compound Ph2C2(NtBu)4Sn
(4). Compounds 1, 2, 3, and 4 were characterized by single-
metathesis reaction of 1 with AgSO3CF3 and (Me3Si)2NLi af- crystal structural analysis. Furthermore, 1 was treated with
forded the formation of PhC(NtBu)2SnOTf (Tf = CF3SO2) (2)
and PhC(NtBu)2SnN(SiMe3)2 (3). The reductive dehalogena-
Fe2(CO)9 to afford the Lewis acid–base adduct 5.
tives can act as good precursors for polymerization and
other catalytic reactions. For example, Gibson et al. showed
that tin(II) compounds performed the role of initiator for
the living polymerization of rac-lactide to heterolactic-en-
riched polylactide.[9a] It is also noteworthy that simple SnII
halides are important promoters for Pt-catalyzed hydro-
formylation.[9b] Moreover, owing to their low toxicity SnII
compounds are preferred over other metal ions for medical
and pharmaceutical applications, for example tin(II) chlor-
ides are important in nuclear medicine as an essential com-
ponent in diagnostic agents used to visualize blood, heart,
lung, kidney, and bone.[9c,9d] In recent years several com-
pounds including Sn(C7H7)[2,6-(CH2NMe2)2C6H3],[8e]
[(nPr)2ATI]SnN3 {[(nPr)2ATI] = N-(n-propyl)-2-(n-propyl-
amino)troponiminate},[8l] Sn[B(C6F5)4]Cp,[10] [Sn(SO3CF3)-
Introduction
There is widespread interest in the chemistry of divalent
derivatives of the heavier group 14 elements, because of
their carbene-like properties.[1] In contrast to carbenes and
silylenes, the germylenes and stannylenes are less reactive
due to the larger energy gap between the s- and p-orbitals.[2]
The germanium analogue of Arduengo’s carbene
(tBuNCHCHNtBu)Ge was obtained by Herrmann et al. in
1992,[3] and presently GeII chemistry is rich and diversified
with different types of germylene derivatives,[4] which have
been reviewed periodically.[5] On the contrary, the tin ana-
logue of the “Arduengo-type carbene” is relatively scant de-
spite the well-known inert pair effect, which proposes that
divalent group 14 species should become more stable upon
descending the group.[6a] Russell et al. recently reported the
synthesis and structural elucidation of five tin analogues
of N-heterocyclic carbene.[6b] Nonetheless, there has been
considerable interest over the past three decades in the
chemistry of dialkyl- and diaryl-SnII compounds following
the pioneering studies by Lappert and co-workers.[7]
Stable tin(II) compounds of formula (SnR2)1,2 and
(RSnX1)1,2 (R = bulky ligand, X1 = halide) are well charac-
terized and are an abundant class of compounds.[8] In con-
trast, derivatives of tin(II) of the type Sn(X2)R, where X2 is
a small ligand other than halide, have received much less
attention. This is surprising, because these tin(II) deriva-
{N(SiMe3)2}]2,[11] (2,6-Trip2C6H3)SnX [Trip
=
2,4,6-
iPr3C6H2; X = Me, N(SiMe3)2], and [{HC(CMeNAr)2}-
SnX] [Ar = 2,6-iPr2C6H3; X = Cl, I, N(SiMe3)2, Me, F,
OTf][12] have been isolated. There is plenty of room for new
discoveries in tin(II) chemistry, and we believe that base-
stabilized heteroleptic stannylenes are particularly attractive
in extending the heavier group 14 analogues of carbene.
In order to explore the chemistry of three-coordinate tin,
it was necessary to design a ligand with the following prop-
erties: (1) easy to synthesize and modify, (2) coordinates
strongly to tin preferably as a bidentate ligand, (3) provides
the opportunity to fine-tune the ligand by altering substitu-
ents. A ligand that fits these criteria is the four-membered
monoanionic amidinato ligand. It has already been em-
ployed as an ancillary ligand in various catalytic conver-
sions, for example oligomerization[13] or polymerization[14]
[a] Institute of Inorganic Chemistry, Georg August University,
37077 Göttingen, Germany
Fax: +49-551-39-3373
E-mail: hroesky@gwdg.de
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Monomeric Divalent Tin(II) Compounds
of olefins or of cyclic esters.[15] The steric and electronic spectrum. The molecular ion peak is observed with the
properties of the amidinato ligand are readily modulated highest relative intensity in the EI mass spectrum at m/z =
through variation of the substituents on the carbon and ni- 385.5.
trogen atoms. Because of the geometric constraints of the
NCN ligand backbone, amidinates have small N–M–N bite
angles. They have a rich coordination geometry in which
both chelating and bridging coordination modes can be
achieved. The balance between chelating and bridging coor-
dination is critically governed by the substitution pattern of
the amidinato ligand. Large substituents on the carbon
atom induce a convergent orientation of the lone pairs (fa-
voring chelation), whereas small substituents lead to a more
parallel orientation of the lone pairs (enabling bridging).[16]
Such ligands have already been utilized in main-group and
transition-metal chemistry.[17] The substituents on the amid-
inate nitrogen atoms can be used for fine-tuning the steric
requirement of the ligand, influencing the coordination ge-
ometry of the metal center. The 2,6-diisopropylphenyl
group has turned out to be very efficient in this respect, and
has been used successfully in the development of stabiliza-
tion of low-valent metal oxidation states.[18] We have found
that the tBu group is also very effective for that purpose.
Recently, we have prepared a few heteroleptic silylenes
[LSiX: X = Cl, OtBu, NMe2, PiPr2; L = PhC(NtBu)2][19]
and gauche-bent silicon(I) and germanium(I) dimers
{[PhC(NtBu)2]2Si2, [PhC(NtBu)2]2Ge2} by taking advan-
tage of such a ligand.[20] Herein we report the preparation
of a compound with a divalent heavier group 14 element,
LSnCl (1) [L = PhC(NtBu)2], and the resulting derivatives,
LSn(OSO2CF3) (2), LSnN(SiMe3)2 (3) and L2Sn (4).
Furthermore, 1 was treated with Fe2(CO)9 to afford
LSnClǞFe(CO)4 (5), a Lewis acid–base adduct.
Maintaining a toluene solution of 1 at –32 °C overnight
resulted in colorless single crystals suitable for X-ray struc-
tural analysis. Compound 1 crystallizes in the triclinic space
¯
group P1 (Figure 1). Compared to the similar structures
[{cy2NC(NAr)2}SnCl] (cy = cyclohexyl), [{(cis-Me2C5H8-
N)C(NAr)2}SnCl][21] and [{tBuC(NAr)2}SnCl][15d] (Ar =
2,6-diisopropylphenyl) the structure of 1 is very similar
showing a distorted trigonal-pyramidal geometry indicating
a stereochemically active lone pair. The bond lengths and
angles are in the same range, but the N–Sn–Cl angles (92.3
and 94.2°) in 1 have slightly smaller values than in the other
structures (94.4–99.8°). The tin atom is 0.20 Å above the
plane of the amidinato ligand. In the other three structures
this value is smaller (0.03–0.12 Å).
Figure 1. Molecular structure of 1. Anisotropic displacement pa-
rameters are depicted at 50% probability level. Hydrogen atoms
are omitted for clarity. Selected bond lengths [Å] and bond angles
[°]: Sn1–N1 2.177(3), Sn1–N3 2.192(3), Sn1–Cl1 2.4831(9); N1–
Sn1–N3 60.5(1), N1–Sn1–Cl1 92.28(7), N3–Sn1–Cl1 94.16(8).
Results and Discussion
The reaction of tert-butylcarbodiimide (tBuN=C=NtBu)
with 1 equiv. of PhLi in diethyl ether followed by treatment
with SnCl2 afforded [PhC(NtBu)2]SnCl (1; Scheme 1).
Compound 1 was obtained as a colorless crystalline solid
in 75% yield, and its structure was confirmed by NMR
spectroscopy, EI mass spectrometry, and elemental analysis.
With the objective of preparing tin(II) derivatives we per-
formed substitution reactions of 1 with selected nucleo-
–
philes. It is well known that the triflate anion (CF3SO3 )
has long served as an excellent leaving group in nucleophilic
displacement reactions.[22] Organotin triflates may act as
precursors for further reactions. Treatment of 1 with AgOTf
in toluene at room temperature for 3 h afforded LSnOTf [L
= PhC(NtBu)2] (2) in good yield (78%) (Scheme 2). Com-
1
pound 2 (Figure 2) was characterized by H, 13C, 19F and
119Sn NMR spectroscopy, EI mass spectrometry and ele-
mental analysis. In the 19F NMR spectrum 2 exhibits a sin-
glet resonance at δ = –73.6 ppm, whereas in the 119Sn NMR
spectrum it resonates at δ = –33.16 ppm. Colorless crystals
of 2 were obtained from a toluene solution at room tem-
perature after 1 d.
Scheme 1. Preparation of 1.
The 1H NMR spectrum of 1 shows a singlet at δ =
1.02 ppm for the 18 protons of two tBu groups and another
The structure of 2 was unequivocally established by X-
multiplet for five aromatic protons (δ = 7.48–7.56 ppm). ray crystallography. Compound 2 crystallizes in the mono-
Compound 1 resonates at δ = 29.6 ppm in the 119Sn NMR clinic space group P21/n. Selected bond lengths and bond
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of 1 with 1 equiv. of LiN(SiMe3)2 in diethyl ether at room
temperature (Scheme 2). Compound 3 (Figure 3) is a white
solid, soluble in benzene, thf, toluene, and shows no decom-
position on exposure to air for a short period of time. The
(amidinato)tin amide is a very interesting compound, be-
cause it can act as a precursor for polymerization and hy-
drolysis reactions. Richeson and his team showed that
(amidinato)tin(II) amide compounds are good catalysts for
cyclotrimerization of phenyl isocyanate to triphenyl iso-
1
cyanurates.[23d,23e] Compound 3 was characterized by H,
13C, 29Si, and 119Sn NMR spectroscopy, EI mass spectrom-
etry, elemental and X-ray structural analysis. The 1H NMR
spectrum of compound 3 shows two singlets (δ = 1.27 and
0.25 ppm) corresponding to tBu and SiMe3 protons respec-
tively, and one multiplet (δ = 7.33–7.45 ppm) for the Ph
protons. The 119Sn NMR spectrum of 3 exhibits a singlet
at δ = –33.58 ppm. The 29Si NMR shows a resonance at δ
= 1.49 ppm. The molecular ion peak is observed with the
highest relative intensity in the EI mass spectrum at m/z =
511.
Scheme 2. Preparation of 2 and 3.
Figure 2. X-ray single-crystal structure of 2. Anisotropic displace-
ment parameters are depicted at 50% probability level. Hydrogen
atoms are omitted for clarity. Selected bond lengths [Å] and bond
angles [°]: Sn1–N1 2.176(2), Sn1–N3 2.163(2), Sn1–O18 2.362(2);
N1–Sn1–N3 60.88(8), N1–Sn1–O18 86.43(8), N3–Sn1–O18
83.09(8).
Figure 3. X-ray single-crystal structure of 3. Anisotropic displace-
ment parameters are depicted at 50% probability level. There are
two molecules in the asymmetric unit. Molecule 1 is shown and
hydrogen atoms are omitted for clarity. Selected bond lengths [Å]
and bond angles [°] for molecule 1: Sn1–N1 2.116(6), Sn1–N10
2.216(6), Sn1–N12 2.227(6); N1–Sn1–N10 103.6(2), N1–Sn1–N12
105.0(2), N10–Sn1–N12 59.9(2); selected bond lengths [Å] and
bond angles [°] for molecule 2 (not shown): Sn2–N1Ј 2.134(5), Sn2–
N10Ј 2.191(7), Sn2–N12Ј 2.214(6), N1Ј–Sn2–N10Ј 102.1(3), N1Ј–
Sn2–N12Ј 106.4(2), N10Ј–Sn2–N12Ј 59.3(2).
angles are given in the caption of Figure 2. The geometry
of the amidinato ligand and the coordination of the tin
atom are similar to what is found in structure 1. However,
the N–Sn–O bond angles are much smaller than the N–Sn–
Cl angles in 1 (83.1 and 86.5 compared to 92.3 and 94.2°).
The distance of the tin atom to the plane of the amidinato
ligand is quite similar (0.23 Å compared to 0.20 Å in 1).
Similar compounds [PhC(NSiMe3)2SnOCPh3], [PhC(NSi-
Me2Ph)2SnOCPh3],[15c] [tBuC(NAr)2SnOiPr][15d] (Ar = 2,6-
iPr2C6H3) show smaller Sn–O bond lengths (2.006–2.040 Å
compared to 2.362 Å in 2), whereas the Sn–N bonds are
An X-ray diffraction study on a single crystal of 3 ob-
longer (2.208–2.252 Å compared to 2.163 and 2.176 Å) and tained from a toluene solution stored at –30 °C in a freezer
the N–Sn–O angles wider (87.3–94.8° compared to 83.1 and for 1 d confirmed the features deduced from the spectro-
86.5°).
scopic data. Compound 3 crystallizes as a pseudomerohed-
Our interest in subvalent group 14 metal bis(trimethylsil- ral twin [twin fraction 0.473(2)] in the triclinic space group
¯
yl)amides derives from work with the isoelectronic bis(tri- P1 with two very similar molecules in the asymmetric unit.
methylsilyl)methyl derivatives and from earlier studies on We find the typical geometry as shown by 1 and 2. But here
many amides, including SnMe3(NMe2).[23] The bis(trimeth- the mean bonds between the tin and amidinato nitrogen
ylsilyl)amido ligand was chosen because (1) its size often atoms (2.21 Å) are longer than the mean values in 1 and 2
stabilizes complexes in which the metal atom has a low co- (2.18 and 2.17 Å). But the value corresponds to those found
ordination number, (2) the numerous methyl groups provide in similar structures: [tBuC(NSiMe3)2SnN(SiMe3)2],[21d]
for good hydrocarbon solubility. Compound LSnN- [tBuC(Ncyclohexyl)2SnN(SiMe3)2][23e] and [tBuC(NAr)2Sn-
(SiMe3)2 (3) was obtained in high yield from the reaction NMe2][15d] (Ar = 2,6-iPr2C6H3) (2.19–2.26 Å) as well as the
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Monomeric Divalent Tin(II) Compounds
average value for the Sn–N (from monodentate amide)
bond (2.13 Å in 3) compared to the two other LSnN-
(SiMe3)2 structures (2.12 and 2.14 Å) and the N–Sn–
NSiMe3 bond angles (102.1–106.4° in 3 compared to 99.0–
105.4°). In these structures the deviation of the tin atom
from the plane of the amidinato ligand is larger (0.5 in 3
and 0.3–0.5 Å in the others) compared to 1 and 2.
Organotin(II) hydrides generally can be prepared by the
reduction of the corresponding chlorides with DIBAL,
AlH3·NMe3 or by direct reaction with H2.[24] Treatment of
1 with AlH3·NMe3 in toluene at room temperature does not
lead to LSnH. However, recently we successfully synthe-
sized L1SnH [L1 = HC(CMeNAr)2; Ar = 2,6-iPr2C6H3] in
good yield and without impurity with the Li[HB(sBu)3]
(commonly known as L-selectride) reagent.[25] Conse-
quently, compound 1 was treated with 1 equiv. of L-se-
lectride, and this resulted in the formation of L2Sn (4)
(Scheme 3). The propensity of the formation of homoleptic
tin compound is due to the instability of the (amidinato)-
Figure 4. Molecular structure of 4. Anisotropic displacement pa-
rameters are depicted at 50% probability level. Hydrogen atoms
are omitted for clarity. Symmetry-related atoms are denoted with
#. Selected bond lengths [Å] and bond angles [°] Sn1–N2 2.195(1),
Sn1–N1 2.394(1); N2–Sn1–N2# 98.12(8), N2–Sn1–N1 57.75(5),
N2#–Sn1–N1 103.97(5), N1–Sn1–N1# 154.24(7).
1
tin(II) hydride. Compound 4 was characterized by H, 13C,
The aptitude of silylene, germylene and stannylene to act
as a σ-donor and π-acceptor already established them as
preeminent ligands for the synthesis of transition-metal
complexes with potential application in homogeneous catal-
ysis.[28] After the successful isolation of chlorostannylene,
we have been intrigued by the question as to whether such
tricoordinate stannylenes can act as ligands to stabilize
metal complexes. Therefore, [PhC(NtBu)2]SnCl and nona-
carbonyldiiron [Fe2(CO)9] were selected as probes to inves-
tigate their reaction behavior. The synthetic procedure
of 5 (Scheme 4) is similar to that of {[PhC(NtBu)2]-
SiOtBu}Fe(CO)4.[28b]
119Sn NMR spectroscopy, EI mass spectrometry, elemental
and X-ray structural analysis. The 1H NMR spectrum exhi-
bits a singlet at δ = 1.12 ppm, which was attributed to 36
protons of tBu groups, and a multiplet (δ = 7.30–7.34 ppm)
assigned to ten protons. The 119Sn NMR spectrum of 4
shows a resonance at δ = –285 ppm, which is upfield
shifted, when compared with that of 1. In the EI mass spec-
trum only peaks of smaller ions are observed. Further
attempts to prepare the Sn–H compound with NaBH4, KH
or NaH failed.
Scheme 3. Preparation of 4.
Maintaining a toluene solution of 4 at –30 °C in a freezer
afforded temperature-sensitive colorless crystals suitable for
X-ray analysis. Compound 4 (Figure 4) crystallizes as a
nonmerohedral twin [twin fraction 0.0252(9)] in the mono-
Scheme 4. Preparation of 5.
Treatment of 1 with 1.2 equiv. of nonacarbonyldiiron in
clinic space group C2/c with half a molecule and a solvent thf for 40 h afforded complex 5. The solvent was then re-
toluene molecule in the asymmetric unit. The coordination moved in vacuo, and the residue was extracted with toluene.
geometry around Sn1 can be viewed as distorted sawhorse- The insoluble solid was filtered off, and the filtrate was con-
like, with N1 and N1# in the axial positions and N2 and centrated to yield a red-brown solid. Complex 5 was charac-
N2# residing in the equatorial plane. Accordingly, the axial terized by NMR spectroscopy, EI mass spectrometry and
Sn–N(1) bond is longer [2.394(1) Å] than the Sn–N(2) bond elemental analysis. In the 119Sn NMR spectrum 5 exhibits
[2.195(1) Å]. There are several known structures with two a sharp resonance (δ = 255 ppm), which indicates the coor-
coordinating amidinato ligands to SnII,[26] for example dination of the Fe to the tin atom resulting in a downfield
[(PhCNSiMe3NtBu)2Sn].[27] All have a more or less dis- chemical shift (119Sn of 1: δ = 29.6 ppm). This downfield
torted sawhorse-like coordination with two longer (2.32– chemical shift suggests the removal of electron density from
2.44 Å) and two shorter bonds (2.15–2.27 Å), but the “ax- the tin atom upon product formation. A similar kind of
ial” angle varies tremendously (119.6–148.8°) showing the downfield chemical shift was observed for the tBu protons
highest value in 4. Accordingly, also the angle between the of the amidinato ligand, which resonate at δ = 1.41 ppm,
planes of the amidinato ligands exhibits a broad range of when compared to those of 1 (δ = 1.02 ppm). In the EI
variation (42.4–89.3°, 53.8° in 4).
mass spectrum the molecular ion appears as the most abun-
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was partially removed (ca. 15 mL) under reduced pressure. Storage
of the remaining solution in a freezer at –32 °C for 2 d afforded
colorless crystals of 2 suitable for X-ray diffraction analyses (0.55 g,
80%). M.p. 135–140 °C. C16H23F3N2O3SSn (500.04): calcd. C
38.50, H 4.64, N 5.61; found C 38.96, H 4.75, N 6.01. 1H NMR
(200 MHz, [D8]thf, 25 °C): δ = 1.08 (s, 18 H, tBu), 7.41–7.48 (m, 5
H, Ph) ppm. 13C{1H}NMR (125.75 MHz, [D8]thf, 25 °C): δ = 32.7
(CMe3), 53.0 (CMe3), 127.3, 127.5, 128.0, 128.4, 128.7, 129.3 (Ph),
168.0 (NCN) ppm. 119Sn NMR (111.92 Hz, [D8]thf, 25 °C): δ =
–33.16 ppm. 19F NMR (188.3 Hz, [D8]thf, 25 °C): δ = –73.6 ppm.
EI-MS: m/z (%) = 500 (100) [M+].
dant peak with highest relative intensity at m/z = 553. All
these data corroborate the formation of 5. Here it is worth
mentioning that 5 can be an efficient precursor for the syn-
thesis of amidinato-stabilized tin(II) hydroxide as we have
shown recently that reaction of L1Sn(NMe2)Fe(CO)4 [L1 =
HC(CMeNAr)2; Ar = 2,6-iPr2C6H3] with H2O gave the first
example of a monomeric tin(II) hydroxide complex of com-
position LSn(OH)Fe(CO)4.[29]
Preparation of Compound 3: Compound 1 and LiN(SiMe3)2 were
placed in a 100 mL Schlenk flask, and diethyl ether (40 mL) was
added at room temperature. The reaction mixture was stirred over-
night. A precipitate was formed and filtered off. The solvent was
partially removed in vacuo. Storage of the remaining solution in a
freezer at –30 °C overnight resulted in colorless crystals of 3 suit-
able for X ray analysis. M.p.120–125 °C. C21H41N3Si2Sn (511.19):
Conclusion
We have prepared monomeric tin(II) chloride stabilized
by a bulky amidinato ligand. By taking advantage of nucleo-
philic substitution reactions using AgOTf or (Me3Si)2NLi,
we synthesized a divalent tin(II) monomer with different
substituents. These compounds can act as good precursors
for catalysis and polymerization reactions. We are currently
exploring their chemistry.
1
calcd. C 49.41, H 8.10, N 8.23; found C 48.96, H 8.33, N 7.56. H
NMR (200 MHz, [D8]thf, 25 °C): δ = 0:25 (s, 18 H, TMS), 1.27 (s,
18 H, tBu), 7.33–7.43 (m,
5
H, Ph) ppm. 13C{1H}NMR
(125.75 MHz, [D8]thf, 25 °C): δ = 25.3 (SiMe3), 32.9 (CMe3), 53.7
(CMe3), 128.2, 128.3, 128.6, 129.1, 129.7, 130.1 (Ph), 169.3 (NCN)
ppm. 119Sn NMR (111.92 Hz, [D8]thf, 25 °C): δ = –33.58 ppm. 29Si
NMR (59.63 Hz, [D8]thf, 25 °C): δ = 1.49 ppm. EI-MS: m/z (%) =
511 (100) [M+].
Experimental Section
Preparation of Compound 4: A solution of Li[HB(sBu)3] in thf
(2.00 mL, 1  in thf) was slowly added drop by drop to a stirred
solution of 1 (1.050 g, 2 mmol) in toluene (30 mL) at –10 °C. The
reaction mixture was warmed to room temperature and then stirred
for an additional 1 h. After removal of all the volatiles, the residue
was extracted with toluene (30 mL), concentrated to 10 mL, and
stored in a freezer at –30 °C. Colorless crystals of 4 were formed
after 1 d. M.p. 135–140 °C. C30H46N2Sn (581.42): calcd. C 65.11,
H 8.38, N 5.06; found C 64.96, H 8.33, N 5.56. 1H NMR
(200 MHz, [D8]thf, 25 °C): δ = 1.08 (s, 36 H, tBu), 7.41–7.48 (m,
10 H, Ph) ppm. 13C{1H}NMR (125.75 MHz, [D8]thf, 25 °C): δ =
31.8 (CMe3), 54.2 (CMe3), 128.6, 128.9, 129.1, 129.9, 130.6, 135.6
(Ph), 173.3 (NCN) ppm. 119Sn NMR (111.92 Hz, [D8]thf, 25 °C):
δ = –285 ppm. EI-MS: m/z (%) = 581 (100) [M+].
General: All manipulations were performed under dry and oxygen-
free N2 by using standard Schlenk techniques or inside an MBraun
MB 150-GI glove box. All solvents were distilled from Na/benzo-
phenone prior to use. Chemicals were purchased commercially and
used as received. 1H, 13C, 19C and 119Sn NMR spectra were re-
corded with a Bruker Avance DRX 500 MHz instrument and refer-
enced to the deuterated solvent in the case of the 1H and 13C NMR
spectra. 19F and 29Si NMR spectra were referenced to BF3·Et2O
and SiMe4, and those of 119Sn NMR to SnMe4. Elemental analyses
were performed by the Analytisches Labor des Instituts für Anor-
ganische Chemie der Universität Göttingen. EI mass spectra were
measured with a Finnigan Mat 8230 or a Varian MAT CH5 instru-
ment. Melting points were measured in sealed glass tubes with a
Buchi melting point B 450 instrument.
Preparation of Compound 5: thf (30 mL) was added to a mixture of
1 (0.4 g, 1.03 mmol) and nonacarbonyldiiron (0.45 g, 1.23 mmol)
at ambient temperature under N2. After stirring for 40 h, the ini-
tially light-orange solution became darker to ultimately afford a
garnet-brown solution. The solvent was then removed in vacuo,
and the residue was extracted with toluene (30 mL). The insoluble
solid was filtered off. The garnet-brown filtrate was concentrated
and stored at –30 °C to yield a red-brown solid of 5 (0.52 g, 61%).
M.p. 182–189 °C. C19H23ClFeN2O4Sn (553.40): calcd. C 41.24, H
Preparation of Compound 1: PhLi (6.86 mL, 13.72 mmol, 1.8  in
diethyl ether) was added to a solution of tBuN=C=NtBu (2.12 g,
13.72 mmol) in diethyl ether (80 mL) in a 200 mL Schlenk flask at
–78 °C. The solution was warmed to ambient temperature and
stirred for 4 h. The solution was added drop by drop to a stirred
suspension of SnCl2 (3.18 g, 13.72 mmol) in diethyl ether (20 mL)
at –78 °C. The reaction mixture was warmed to room temperature
and stirred for 24 h. The precipitate was filtered off, and, after re-
moval of all volatiles in vacuo, the residue was extracted with tolu-
ene (20 mL). Storage of the extract at –32 °C in a freezer for 1 d
afforded colorless crystals of 1. M.p. 135–140 °C. C15H23ClN2Sn
(385.52): calcd. C 46.73, H 6.01, N 7.27; found C 46.96, H 6.33, N
1
4.19, N 5.06; found C 43.51, H 5.33, N 4.85. H NMR (200 MHz,
[D8]thf, 25 °C): δ = 1.41 (s, 18 H, tBu), 7.56–7.82 (m, 5 H, Ph) ppm.
13C{1H}NMR (125.75 MHz, [D8]thf, 25 °C): δ = 31.3 (CMe3), 54.9
(CMe3), 127.8, 128.2, 128.3, 129.2, 130.0, 130.7 (Ph), 171.1 (NCN),
220.5 (CO) ppm. 119Sn NMR (111.92 Hz, [D8]thf, 25 °C): δ =
255 ppm. EI-MS: m/z (%) = 553 (100) [M+].
1
7.56. H NMR (200 MHz, [D8]thf, 25 °C): δ = 1.02 (s, 18 H, tBu),
7.41–7.48 (m, 5 H, Ph) ppm. 13C{1H}NMR (125.75 MHz, [D8]thf,
25 °C): δ = 31.8 (CMe3), 54.2 (CMe3), 128.6, 128.9, 129.1, 129.9,
130.6, 135.6 (Ph), 173.3 (NCN) ppm. 119Sn NMR (111.92 Hz, [D8]-
thf, 25 °C): δ = 29.6 ppm. EI-MS: m/z (%) = 385.5 (100) [M+].
Crystal Structure Determination: The data for structures 1, 2, 3,
and 4 were collected with a Bruker three-circle diffractometer
equipped with a SMART 6000 CCD detector and a mirror-system-
monochromated Cu-Kα source. The data were integrated with
SAINT, and a semi-empirical absorption correction with SADABS
Preparation of Compound 2: A solution of 1 (0.385 g, 1.0 mmol) in
toluene (20 mL) was added to a stirred suspension of AgSO3CF3
(0.257 g, 1.0 mmol) in toluene (10 mL) at room temperature and was applied.[30,31] The structures were solved by direct methods
was stirred for 4 h. The precipitate was filtered off, and the solvent
(SHELXS-97)[32] and refined against all data by full-matrix least-
5308
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© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2010, 5304–5311

Monomeric Divalent Tin(II) Compounds
Table 1. Crystallographic data for the X-ray structural analyses of compounds 1, 2, 3 and 4.
1
2
3
4
Empirical formula
Formula mass
C15H23ClN2Sn
385.49
C16H23F3N2O3SSn
499.14
C21H41N3Si2Sn
510.44
C44H62N4Sn
765.67
T [K]
Crystal system
CCDC no.
Space group
100(2)
triclinic
100(2)
monoclinic
780256
100(2)
triclinic
100(2)
monoclinic
780258
780255
780257
¯
¯
P1
P21/n
P1
C2/c
a [Å]
b [Å]
c [Å]
α [°]
6.0640(10)
10.309(2)
13.705(2)
85.4310(10)
80.1550(10)
84.060(2)
837.9(2)
2
9.737(2)
21.101(3)
10.218(2)
90
106.09(2)
90
2017.2(6)
4
1.643
11.317(2)
17.526(4)
13.602(3)
90.03(3)
104.50(3)
89.98(3)
2611.9(9)
4
10.179(2)
16.519(3)
24.900(4)
90
98.06(2)
90
4145.5(13)
4
1.226
β [°]
γ [°]
V [Å3]
Z
ρcalcd. [Mgm–3]
1.528
13.498
1.298
8.725
µ [mm–1]
11.457
5.140
F(000)
Reflections collected
R(int)
388
8315
0.0383
1000
16964
0.0404
1064
46091
0.0505
1616
27483
0.0384
Data/restraints/parameters
GooF
2337/175/219
1.129
R1 = 0.0236,
wR2 = 0.0583
R1 = 0.0237,
wR2 = 0.0583
3140/0/241
1.034
R1 = 0.0252,
wR2 = 0.0666
R1 = 0.0263,
wR2 = 0.0684
0.851/–0.620
10192/0/513
1.163
R1 = 0.0476,
wR2 = 0.1259
R1 = 0.0501,
wR2 = 0.1295
1.573/–2.389
3516/57/230
1.057
R1 = 0.0205,
wR2 = 0.0502
R1 = 0.0211,
wR2 = 0.0504
0.376/–0.252
R1, wR2[I Ͼ 2σ(I)][a]
R1, wR2 (all data)[b]
Largest difference peak/hole [e Å–3] 0.650/–0.693
[a] R1 = Σ||Fo| – |Fc||/Σ|Fo|. [b] wR2 = [Σw(Fo – Fc ) /Σw(Fo2)2]0.5
.
2
2 2
squares methods on F2 (SHELXL-97).[33] All non-hydrogen atoms
were refined with anisotropic displacement parameters. The hydro-
gen atoms were refined isotropically on calculated positions by
using a riding model with their Uiso values constrained to 1.5·Uequ
of their pivot atoms for terminal sp3 carbon atoms and 1.2 times
for all other carbon atoms. In compound 1 one tBu group was
modelled in two conformations [occupancy of the minor compo-
nent was refined to 0.40(1)]. The disordered group was refined with
distance restraints and restraints for the anisotropic displacement
parameters. The structure of 3 was refined as a pseudomerohedral
[1]
[2]
J. Barrau, G. Rima, Coord. Chem. Rev. 1998, 178–180, 593–
622.
a) P. Jutzi, H. J. Hoffmann, D. J. Brauer, C. Krüger, Angew.
Chem. 1973, 85, 1116–1117; Angew. Chem. Int. Ed. Engl. 1973,
12, 1002–1003; b) S. R. Stobart, J. Chem. Soc., Chem. Com-
mun. 1979, 911–912.
[3]
[4]
W. A. Herrmann, M. Denk, J. Behm, W. Scherer, F.-R. Klin-
gan, H. Bock, B. Solouki, M. Wagner, Angew. Chem. 1992, 104,
1489–1492; Angew. Chem. Int. Ed. Engl. 1992, 31, 1485–1488.
a) H. V. R. Dias, Z. Wang, J. Am. Chem. Soc. 1997, 119, 4650–
4655; b) J. Barrau, G. Rima, T. E. Amraoui, Organometallics
1998, 17, 607–614; c) A. E. Ayers, D. S. Marynick, H. V. R.
Dias, Inorg. Chem. 2000, 39, 4147–4151; d) N. N. Zemlyansky,
I. V. Borisova, M. G. Kuznetsova, V. N. Khrustalev, Y. A. Us-
tynyuk, M. S. Nechaev, V. V. Lunin, J. Barrau, G. Rima, Orga-
nometallics 2003, 22, 1675–1681; e) M. Driess, N. Dona, K.
Merz, Dalton Trans. 2004, 3176–3177; f) V. N. Khrustalev, I. A.
Portnyagin, N. N. Zemlyansky, I. V. Borisova, Y. A. Ustynyuk,
M. Yu. Antipin, J. Organomet. Chem. 2005, 690, 1056–1062;
g) V. N. Khrustalev, I. A. Portnyagin, N. N. Zemlyansky, I. V.
Borisova, M. S. Nechaev, Y. A. Ustynyuk, M. Yu. Antipin, V.
Lunin, J. Organomet. Chem. 2005, 690, 1172–1177.
a) M. Veith, Angew. Chem. 1987, 99, 1–14; Angew. Chem. Int.
Ed. Engl. 1987, 26, 1–14; b) W. P. Neumann, Chem. Rev. 1991,
91, 311–334; c) H. V. R. Dias, Z. Wang, W. Jin, Coord. Chem.
Rev. 1998, 176, 67–86; d) K. W. Klinkhammer in The Chemistry
of Organic Germanium, Tin and Lead Compounds (Ed.: Z. Rap-
poport), Wiley, New York, 2002, vol. 2, pp. 284–332; e) O.
Kühl, Coord. Chem. Rev. 2004, 248, 411–427; f) I. Saur, S. G.
Alonso, J. Barrau, Appl. Organomet. Chem. 2005, 19, 414–428;
g) W.-P. Leung, K.-W. Kan, K.-H. Chong, Coord. Chem. Rev.
2007, 251, 2253–2265; h) S. Nagendran, H. W. Roesky, Organo-
metallics 2008, 27, 457–492.
¯
twin [twin fraction 0.473(2)] in space group P1 with two molecules
in the asymmetric unit. Also a refinement in space group P21/c
with a disordered model was possible, but showed the following
features: systematic absence violations, high residual density peak
of 0.75 eÅ–3, higher R1 and wR2 values, higher standard uncer-
tainties for bond lengths and angles, strange proposed weighting
2
scheme high K (mean Fo2/Fc ) for the reflections with the lowest
intensities. Compound 4 crystallizes as a nonmerohedral twin [twin
fraction 0.0252(9)] in the monoclinic space group C2/c. The twin
law is a twofold rotation about the real axis 001. Crystallographic
data for the X-ray structural analyses of compounds 1, 2, 3, and 4
are given in Table 1. CCDC-780255 (for 1), -780256 (for 2), -780257
(for 3) and -780258 (for 4) contain the supplementary crystallo-
graphic data for this paper. These data can be obtained free of
charge from The Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/datarequest/cif.
[5]
Acknowledgments
We are thankful to the Deutsche Forschungsgemeinschaft for sup-
porting this work. S. N. thanks the Alexander von Humboldt Stif-
tung for a research fellowship.
[6]
a) T. Gans-Eichler, D. Gudat, M. Nieger, Angew. Chem. 2002,
114, 1966–1969; Angew. Chem. Int. Ed. 2002, 41, 1888–1892;
Eur. J. Inorg. Chem. 2010, 5304–5311
© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
5309

H. W. Roesky et al.
FULL PAPER
b) S. M. Manshell, C. A. Russell, D. F. Wass, Inorg. Chem.
2008, 47, 11367–11375.
temeyer, H.-G. Schmidt, M. Shmulinson, M. S. Eisen, J. Mol.
Catal. A 1998, 130, 149–162; l) D. Walther, R. Fischer, H.
Görls, J. Koch, B. Schweder, J. Organomet. Chem. 1996, 508,
13–22; m) S. Bambirra, M. W. Bouwkamp, A. Meetsma, B.
Hessen, J. Am. Chem. Soc. 2004, 126, 9182–9183.
a) B. J. O’Keefe, L. E. Breyfogle, M. A. Hillmyer, W. B. Tol-
man, J. Am. Chem. Soc. 2002, 124, 4384–4393; b) K. B. Aub-
recht, K. Chang, M. A. Hillmyer, W. B. Tolman, J. Polym. Sci.
A: Polym. Chem. 2001, 39, 284–293; c) K. B. Aubrecht, M. A.
Hillmyer, W. B. Tolman, Macromolecules 2002, 35, 644–650; d)
N. Nimitsiriwat, V. C. Gibson, E. L. Marshall, A. J. P. White,
S. H. Dale, M. R. J. Elsegood, Dalton Trans. 2007, 4464–4471.
a) S. Hao, S. Gambarotta, C. Bensimon, J. J. H. Edema, Inorg.
Chim. Acta 1993, 213, 65–74; b) M. P. Coles, D. C. Swenson,
R. F. Jordan, V. G. Young Jr, Organometallics 1997, 16, 5183–
5194.
[7]
a) M. F. Lappert, P. P. Power, A. R. Sanger, R. C. Srivastava in
Metal and Metalloid Amides, Ellis Horwood Ltd., Chichester,
1980; b) M. F. Lappert, Main Group Met. Chem. 1994, 17, 183–
207; c) W. P. Neumann, Chem. Rev. 1991, 91, 311–334; d) M.
Driess, H. Grützmacher, Angew. Chem. 1996, 108, 900–929;
Angew. Chem. Int. Ed. Engl. 1996, 35, 828–856; e) M. Weiden-
bruch, Eur. J. Inorg. Chem. 1999, 373–381; f) N. Tokitoh, R.
Okazaki, Coord. Chem. Rev. 2000, 210, 251–277; g) S. E.
Boganov, M. V. Egorov, V. I. Faustov, O. M. Nefedov in The
Chemistry of Organic Germanium, Tin and Lead Compounds
(Ed.: Z. Rappoport), Wiley, New York, 2002, vol. 2, pp. 749–
839.
Selected examples: a) M. P. Bigwood, P. J. Corvan, J. J. Zucker-
man, J. Am. Chem. Soc. 1981, 103, 7643–7646; b) R. West,
Science 1984, 225, 1109–1114; c) G. Raabe, J. Michl, Chem.
Rev. 1985, 85, 419–509; d) L. M. Engelhardt, B. S. Jolly, M. F.
Lappert, C. L. Raston, A. H. White, J. Chem. Soc., Chem.
Commun. 1988, 336–337; e) J. T. B. H. Jastrzebski, P. A.
van der Schaaf, J. Boersma, G. van Koten, M. C. Zoutberg, D.
Heijdenrijk, Organometallics 1989, 8, 1373–1375; f) C. Eaborn,
K. Izod, P. B. Hitchcock, S. E. Sözerli, J. D. Smith, J. Chem.
Soc., Chem. Commun. 1995, 1829–1830; g) R. Okazaki, R.
West, Adv. Organomet. Chem. 1996, 39, 231–273; h) K. M.
Baines, W. G. Stibbs, Adv. Organomet. Chem. 1996, 39, 275–
324; i) C. Drost, P. B. Hitchcock, M. F. Lappert, L. J. Pierssens,
Chem. Commun. 1997, 1141–1142; j) P. B. Hitchcock, M. F.
Lappert, M. Layh, Inorg. Chim. Acta 1998, 269, 181–190; k)
L. Pu, M. M. Olmstead, P. P. Power, B. Schiemenz, Organome-
tallics 1998, 17, 5602–5206; l) A. E. Ayers, D. S. Marynick,
H. V. R. Dias, Inorg. Chem. 2000, 39, 4147–4151.
[15]
[16]
[17]
[8]
a) C. A. Nijhuis, E. Jellema, T. J. J. Sciarone, A. Meetsma,
P. H. M. Budzelaar, B. Hessen, Eur. J. Inorg. Chem. 2005, 2089–
2099; b) F. T. Edelmann, Coord. Chem. Rev. 1994, 137, 403–
481; c) J. Barker, M. Kilner, Coord. Chem. Rev. 1994, 133, 219–
300.
[18]
[19]
a) S. P. Green, C. Jones, P. C. Junk, K.-A. Lappert, A. Stasch,
Chem. Commun. 2006, 3978–3980; b) C. Jones, P. C. Junk, J. A.
Platts, A. Stasch, J. Am. Chem. Soc. 2006, 128, 2206–2207; c)
S. P. Green, C. Jones, A. Stasch, Science 2007, 318, 1754–1757;
d) C.-W. Hsu, J.-S. K. Yu, C.-H. Yen, G.-H. Lee, Y. Wang, Y.-
C. Tsai, Angew. Chem. 2008, 120, 10081–10084; Angew. Chem.
Int. Ed. 2008, 47, 9933–9936; e) R. P. Rose, C. Jones, C. Schul-
ten, S. Aldridge, A. Stasch, Chem. Eur. J. 2008, 14, 8477–8480.
a) C.-W. So, H. W. Roesky, J. Magull, R. B. Oswald, Angew.
Chem. 2006, 118, 4052–4054; Angew. Chem. Int. Ed. 2006, 45,
3948–3951; b) C.-W. So, H. W. Roesky, P. M. Gurubasavaraj,
R. B. Oswald, M. T. Gamer, P. G. Jones, S. Blaurock, J. Am.
Chem. Soc. 2007, 129, 12049–12054; c) S. S. Sen, H. W. Roesky,
D. Stern, J. Henn, D. Stalke, J. Am. Chem. Soc. 2010, 132,
1123–1126.
a) S. Nagendran, S. S. Sen, H. W. Roesky, D. Koley, H.
Grubmüller, A. Pal, R. Herbst-Irmer, Organometallics 2008,
27, 5459–5463; b) S. S. Sen, A. Jana, H. W. Roesky, C. Schul-
zke, Angew. Chem. 2009, 121, 8688–8690; Angew. Chem. Int.
Ed. 2009, 48, 8536–8538.
M. Brym, M. D. Francis, G. Jin, C. Jones, D. P. Mills, A.
Stasch, Organometallics 2006, 25, 4799–4807.
R. D. Howells, J. D. Mc Cown, Chem. Rev. 1977, 77, 69–92.
a) D. H. Harris, M. F. Lappert, J. B. Pedley, G. J. Sharp, J.
Chem. Soc., Dalton Trans. 1976, 945–949; b) M. J. S. Gyenane,
D. H. Harris, M. F. Lappert, P. P. Power, P. Rivière, M. Rivière-
Baudet, J. Chem. Soc., Dalton Trans. 1977, 2004–2009; c) K.
Jones, M. F. Lappert in Organotin Compounds (Ed.: A. K. Saw-
yer), Marcel Dekker, New York, 1971, vol. 2, ch. 7; d) S. R.
Foley, Y. Zhou, G. P. A. Yap, D. S. Richeson, Inorg. Chem.
2000, 39, 924–929; e) S. R. Foley, G. P. A. Yap, D. S. Richeson,
Organometallics 1999, 18, 4700–4705.
a) B. E. Eichler, P. P. Power, J. Am. Chem. Soc. 2000, 122, 8785–
8786; b) L. W. Pineda, V. Jancik, K. Starke, R. B. Oswald,
H. W. Roesky, Angew. Chem. 2006, 118, 2664–2667; Angew.
Chem. Int. Ed. 2006, 45, 2602–2605; c) E. Rivard, R. C. Fi-
scher, R. Wolf, Y. Peng, W. A. Merrill, N. D. Schley, Z. Zhu,
L. Pu, J. C. Fettinger, S. J. Teat, S. Nowik, R. H. Herber, N.
Takagi, S. Nagase, P. P. Power, J. Am. Chem. Soc. 2007, 129,
16197–16208; d) Y. Peng, B. D. Ellis, X. Wang, P. P. Power, J.
Am. Chem. Soc. 2008, 130, 12268–12269.
[9]
a) A. P. Dove, V. C. Gibson, E. L. Marshall, A. J. P. White, D. J.
Williams, Chem. Commun. 2001, 283–284; b) M. S. Holt, W. L.
Wilson, J. H. Nelson, Chem. Rev. 1989, 89, 11–49; c) M. D.
Francis, A. J. Tofe, R. A. Hiles, C. G. Birch, J. A. Bevan, R. J.
Grabenstetter, Int. J. Nucl. Med. Biol. 1981, 8, 145–152; d) H. I.
Popescu, J. Lessem, M. Erjavec, G. F. Fuger, Eur. J. Nucl. Med.
1984, 9, 295–299.
[20]
[21]
[10]
[11]
[12]
R. J. Batchelor, J. N. R. Ruddick, J. R. Sams, F. Aubke, Inorg.
Chem. 1977, 16, 1414–1417.
P. B. Hitchcock, M. F. Lappert, G. A. Lawless, G. M. Lima,
L. J. Pierssens, J. Organomet. Chem. 2000, 601, 142–146.
a) L. Pu, M. M. Olmstead, P. P. Power, B. Schiemenz, Organo-
metallics 1998, 17, 5602–5606; b) B. E. Eichler, P. P. Power, In-
org. Chem. 2000, 39, 5444–5449; c) Y. Ding, H. W. Roesky, M.
Noltemeyer, H.-G. Schmidt, P. P. Power, Organometallics 2001,
20, 1190–1194; d) A. Jana, H. W. Roesky, C. Schulzke, A.
Döring, T. Beck, A. Pal, R. Herbst-Irmer, Inorg. Chem. 2009,
48, 193–197.
a) E. A. C. Brussee, A. Meetsma, B. Hessen, J. H. Teuben,
Chem. Commun. 2000, 497–498; b) E. A. C. Brussee, A.
Meetsma, B. Hessen, J. H. Teuben, Organometallics 1998, 17,
4090–4095.
a) C. Averbuj, E. Tish, M. S. Eisen, J. Am. Chem. Soc. 1998,
120, 8640–8646; b) V. Volkis, M. Shmulinson, C. Averbuj, A.
Lisovskii, F. T. Edelmann, M. S. Eisen, Organometallics 1998,
17, 3155–3157; c) S. Bambirra, D. van Leusen, A. Meetsma,
J. H. Teuben, Chem. Commun. 2003, 522–523; d) M. J. R.
Brandsma, E. A. C. Brussee, A. Meetsma, B. Hessen, J. H.
Teuben, Eur. J. Inorg. Chem. 1998, 1867–1870; e) M. P. Coles,
R. F. Jordan, J. Am. Chem. Soc. 1997, 119, 8125–8126; f) J. M.
Decker, S. J. Geib, T. Y. Meyer, Organometallics 1999, 18, 4417–
4420; g) J. C. Flores, J. C. W. Chien, M. D. Rausch, Organome-
tallics 1995, 14, 1827–1833; h) D. Herskovics-Korine, M. S.
Eisen, J. Organomet. Chem. 1995, 503, 307–314; i) R. J. Keaton,
K. C. Jayaratne, D. A. Henningsen, L. A. Koterwas, L. R. Sita,
J. Am. Chem. Soc. 2001, 123, 6197–6198; j) K. C. Jayaratne,
R. J. Keaton, D. A. Henningsen, L. R. Sita, J. Am. Chem. Soc.
2000, 122, 10490–10491; k) J. Richter, F. T. Edelmann, M. Nol-
[22]
[23]
[13]
[14]
[24]
[25]
A. Jana, D. Ghoshal, H. W. Roesky, I. Objartel, G. Schwab, D.
Stalke, J. Am. Chem. Soc. 2009, 131, 1288–1293.
[26]
[27]
F. A. Allen, Acta Crystallogr., Sect. B 2002, 58, 380–388.
F. Antolini, P. B. Hitchcock, A. V. Khvostov, M. F. Lappert,
Can. J. Chem. 2006, 84, 269–276.
a) M. Haaf, R. Hayashi, R. West, J. Chem. Soc., Chem. Com-
mun. 1994, 33–34; b) W. Yang, H. Fu, H. Wang, M. Chen, Y.
Ding, H. W. Roesky, A. Jana, Inorg. Chem. 2009, 48, 2058–
[28]
5310
www.eurjic.org
© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2010, 5304–5311

Monomeric Divalent Tin(II) Compounds
2060; c) J. Li, S. Merkel, J. Henn, K. Meindl, A. Döring, H. W.
Roesky, R. S. Ghadwal, D. Stalke, Inorg. Chem. 2010, 49, 775–
777; d) A. Meltzer, C. Präsang, M. Driess, J. Am. Chem. Soc.
2009, 131, 7232–7233; e) S. Inoue, M. Driess, Organometallics
2009, 28, 5032–5035; f) X. J. Yang, Y. Wang, B. Quillian, P.
Wei, Z. Chen, P. v. R. Schleyer, G. H. Robinson, Organometal-
lics 2006, 25, 925–929.
[30] SAINT-NT, Bruker AXS, Inc., Madison, Wisconsin, USA,
2000.
[31] G. M. Sheldrick, SADABS 2.0, University of Göttingen, Ger-
many, 2000.
[32] SHELXS-90, Program for Structure Solution: G. M. Sheldrick,
Acta Crystallogr., Sect. A 1990, 46, 467–473.
[33] SHELXL-97, Program for Crystal Structure Refinement:
G. M. Sheldrick, Acta Crystallogr., Sect. A 2008, 64, 112–122.
Received: July 26, 2010
[29] A. Jana, S. P. Sarish, H. W. Roesky, C. Schulzke, P. P. Samuel,
Chem. Commun. 2010, 46, 707–709.
Published Online: October 20, 2010
Eur. J. Inorg. Chem. 2010, 5304–5311
© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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