Novel germylenes and stannylenes based on pyridine-containing dialcohol ligands

Article abstract of DOI:10.1016/j.jorganchem.2009.06.039

The reactions between M[N(SiMe₃)₂]₂ (M = Ge, Sn) and three pyridine-based dialcohols yielded germylenes and stannylenes 1-6. The composition and structures of the novel compounds were established by elemental analyses, ¹H and ¹³C NMR spectroscopy. The structures of insoluble species were confirmed by conversion to the corresponding dibromides 7-9. The single crystal structures of stannylene 4 and germylene 5 were determined by X-ray diffraction analyses. The germanium compound was found to be monomeric whilst the tin compound is a dimer. Both compounds possess strong transannular MN interaction in the solid phase.

Full text of DOI:10.1016/j.jorganchem.2009.06.039

Journal of Organometallic Chemistry 694 (2009) 3828–3832
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Note
Novel germylenes and stannylenes based on pyridine-containing dialcohol ligands
Mengmeng Huang a, El’mira Kh. Lermontova b, Kirill V. Zaitsev a, Andrei V. Churakov b, Yuri F. Oprunenko a,
a
Judith A.K. Howard c, Sergey S. Karlov a, , Galina S. Zaitseva
*
a Chemistry Department, Moscow State University, B-234 Leninskie Gory, 119899 Moscow, Russia
b Institute of General and Inorganic Chemistry, RAS, Leninskii Pr. 31, Moscow 119991, Russia
c Department of Chemistry, University of Durham, South Road, DH1 3LE Durham, UK
a r t i c l e i n f o
a b s t r a c t
Article history:
The reactions between M[N(SiMe3)2]2 (M = Ge, Sn) and three pyridine-based dialcohols yielded germyl-
enes and stannylenes 1–6. The composition and structures of the novel compounds were established by
elemental analyses, 1H and 13C NMR spectroscopy. The structures of insoluble species were confirmed by
conversion to the corresponding dibromides 7–9. The single crystal structures of stannylene 4 and ger-
mylene 5 were determined by X-ray diffraction analyses. The germanium compound was found to be
monomeric whilst the tin compound is a dimer. Both compounds possess strong transannular MN inter-
action in the solid phase.
Received 24 February 2009
Received in revised form 16 June 2009
Accepted 29 June 2009
Available online 2 July 2009
Keywords:
Germylenes
Stannylenes
Ó 2009 Elsevier B.V. All rights reserved.
Molecular main-group-element compounds
Germanium
Tin
1. Introduction
Germylenes and stannylenes of the formulas M(OR)2 and
M(NR2)2 are able to exist in dimeric state where the metal atoms
The carbene analogues of heavier group 14 elements are com-
pounds of the general formula R–M–R0 (R and R0 = any monovalent
substituent; M = Si, Ge, Sn, or Pb). Although these compounds were
known before (see for example, the synthesis of Cp2Sn in 1956 [1]
and the review concerning the reactivity of unstable silylenes [2]),
they have been a focus of theoretical and experimental interest
since the early 1970s when stable dialkyl and diamido derivatives
of Ge, Sn, and Pb were prepared by Lappert and co-workers [3].
Since then, several reviews dealing with preparation, chemical
properties and structures of these compounds were published
[4]. It was demonstrated that many of these compounds are rela-
tively stable and may be studied as ‘‘usual” molecular substances
by appropriate techniques. Several factors stabilizing the low-va-
lent metal centre were found, one of them was the electron stabil-
ization resulting from intramolecular interaction of metal centre
of one monomeric unit form additional bond with O or N atoms
of the other unit [8]. One can suggest that these dimers have less
reactivity than monomeric ‘‘heavier” carbenes. Obviously, small li-
gands bonded to metal atoms promote dimerization of target
germylenes and stannylenes, whereas bulky ligands stabilize the
monomeric form. However, at the moment there are just few sys-
tematic investigations on the balance between steric volume of li-
gands and the structure of germylenes (stannylenes) [8e]. In
addition, very bulky ligands decrease the reactivity of such com-
pounds, as it was recently found for bulky carbenes. The transition
metal complexes with such carbene ligands possess poor catalytic
activity [9].
To our opinion, dialkanolamines are very promising ligands for
stabilization of monomeric structures of germylenes and stannyl-
enes due to the following factors: a) possible additional transannu-
lar interaction with nitrogen atom of the ligands; b) the possibility
to design easily the structure of such ligands, for instance, replacing
the H atoms of methylene groups with different substituents. In
spite of this, dialkanolamines were not previously studied as li-
gands for germylenes and stannylenes except the preparation of
MeN(CH2CH2O)2Ge [10] and MeN(CH2CH2O)2Sn [11]. When this re-
port was under review the report of Jurkschat et al. on X-ray study
of dimeric [MeN(CH2CH2O)2Sn]2 was published [11c]. It should be
noted that recently monoalkanolamine ligand Me2NCH2CH2O–
was used to stabilize stannylene and germylene compounds [12].
with
p-donors covalently bonded to the metal atom (–OR, –NR2
group) or additional transannular interaction of metal centre with
a donor group [5]. The preparation of these compounds allowed to
study in details the structure and reactivity of heavier group 14
element carbene analogues [6]. These compounds may represent
the promising ligands for transition metal catalysts [7].
* Corresponding author. Tel.: +7 4959393887; fax: +7 4959328846.
E-mail address: sergej@org.chem.msu.ru (S.S. Karlov).
0022-328X/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2009.06.039

M. Huang et al. / Journal of Organometallic Chemistry 694 (2009) 3828–3832
3829
Here we present the synthesis and structural investigations of a
series of novel germylenes and stannylenes 1–6 based on pyridine-
containing dialcohol ligands (dialkanolamine analogues) of differ-
ent size. It should be noted that this kind of ligands have already
been used for preparation of group 14 element (M+4) derivatives
[13]. Compounds 4 and 5 are the first structurally characterised
germylenes and stannylenes based on dialcohol ligands with N-
containg functional group except dimeric [MeN(CH2CH2O)2Sn]2
(see above and [11c]). The reactions of the ‘‘heavier” carbenes
(1–3) with bromine led to Ge+4 and Sn+4 derivatives 7–9. Further
design of these ligands will allow the discriminative preparation
of closely related germylenes and stannylenes as monomeric or di-
meric species with different chemical behaviour.
ously, dimers). On the contrary, the reaction of Ge[N(SiMe3)2]2
with 2,6-(pyridine)dimethanol led to insoluble compound ‘‘Py
(CH2O)2Ge‘‘, which does not led to expected Py(CH2O)2GeBr2 in
the reaction with bromine. This dibromide was previously ob-
tained in another way [13e]. We can suppose that ‘‘Py(CH2O)2Ge‘‘
has a polymer structure. Consequently, the presence of substitu-
ents at carbon atoms is necessary for the existence of germylenes
and stannylenes in monomeric or dimeric form.
To the best of our knowledge compounds 4 and 5 are the first
derivatives of tin(II) (except dimeric [MeN(CH2CH2O)2Sn]2 [11c])
and germanium(II) based on dialkanolamine or analogous cage li-
gand that have been structurally characterised. The molecular
structures of 4 and 5 are shown in Figs. 1 and 2. Table 1 summa-
rizes significant geometrical parameters for these compounds.
According to X-ray data, germylene 5 is monomeric in the solid
state. The primary coordination environment of the Ge atom is
formed by two covalent bonded oxygen atoms and one dative
bonded nitrogen atom and may be treated as a trigonal pyramid
with a lone pair in one vertex. To our knowledge, this is the second
example of X-ray studied monomeric germylene with O,N,O coor-
dination environment. The N ? Ge-bond in 5 is comparable with
that in Me2NCH2CH2OGe–OC(O)CH3 (2.108(1) Å) with tricoordi-
nated germanium atom [12c]. The Ge–OCH2 bond length
(1.832(1) Å) in Me2NCH2CH2OGe–OC(O)CH3 is also close to
Ge(1)–O(1) bond distance in 5. It should be noted that the length
of Ge(1)–O(1) bond in 5 is close to the Ge–O bond lengths in
Ge[OC(t-Bu)3]2 (1.896(6) and 1.83(1) Å), which is the only structur-
ally characterised monomeric dialkoxy germylene [16]. Thus, addi-
2. Results and discussion
The reaction between M[N(SiMe3)2]2 and alcohols is a standard
approach to di(alkoxy)germylenes and stannylenes [14]. We used
this method for the synthesis of 1–6 (Scheme 1). The target deriv-
atives were obtained in a moderate or good yields (31-74%). The
structures of the prepared compounds were confirmed by elemen-
tal analysis data and 1H, 13C NMR spectroscopy (for compounds
soluble in ordinary deuterated solvents). 1H, 13C NMR spectra are
in consistency with the suggested structures. According to 119Sn
NMR spectroscopy data (see Experimental part) stannylenes 4
and 6 are dimeric in solution. The latter was confirmed by upfield
drift of 119Sn resonance resulted from additional base coordination
on tin centre in dimeric structure [15]. According to data of 1H and
13C NMR spectroscopy hydrogen atoms of CH2 groups in ‘‘heavier
carbenes” 3 and 4 as well as phenyl groups in the same compounds
are magnetically non-equivalent. At the same time, phenyl groups
in 1 are magnetically equivalent. We can suppose that there is not
dynamic processes in this compound at room temperature due to
the presence of pyridine ring and the strong intramolecular inter-
action metal–nitrogen in these compounds. To our opinion the
main reason of this difference is different conformations of six-
membered (3 and 4, @C–C–C–O–Ge N@) and five-membered (1,
@C–C–O–Ge N@, all atoms lie in the same plane) rings.
tional intramolecular interaction in
5 does not considerably
elongate the Ge–O bonds. Of interest, the germanium atom in 5 lies
almost in the plane of pyridine ring. The GeAN bond is nearly
perpendicular to the O-Ge-O plane, allowing ideal interaction of
nitrogen lone electron pair with the vacant Ge orbital.
In contrast to 5, closely related stannylene 4 is dimeric in the so-
lid state (as well as in benzene solution, see above). The dimeriza-
tion results from the formation of an additional bond between the
tin atom of one monomeric unit and the oxygen atom of the other.
The central (Sn–O)2 units are non-planar and form a puckered rect-
angle with a pseudo-twofold axis passing through the centre. Non-
coordinated oxygen atoms occupy cis-positions relative to (Sn–O)2
core. The same cis-configuration was found in [MeN(CH2-
CH2O)2Sn]2 [11c]. The coordination polyhedron of the Sn atom in
compound 4 represents a distorted tetragonal pyramid with three
oxygen atoms and nitrogen atom in the base of the pyramid and a
lone pair in its vertex. The Sn–N bond length in 4 is close to that
previously found in N3Sn(OCH2CH2)NMe2 (2.505(5) Å) [12b],
(Me3Si)2N–Sn(OCH2CH2)NMe2 (2.617(3), 2.615(3) Å) and [MeN
(CH2CH2O)2Sn]2 (2.41(1), 2.45(1) Å) [11c] which are dimeric due
to Sn–O bond formation [12d]. The central (Sn–O)2 unit possesses
two different pairs of Sn–O bond: Sn(1)–O(4) (2.183(3) Å) and
Sn(2)–O(2) (2.182(3) Å) may be considered as covalent and Sn(1)–
O(2) bond (2.355(3) Å) and Sn(2)–O(4) (2.301(3) Å) are dative.
Two other non-coordinative Sn–O bonds are considerably shorter:
2.058(3) and 2.064(3) Å. Analogous correlation of Sn–O bond
lengths were found in [MeN(CH2CH2O)2Sn]2 [11c].
In conclusion, metathetical exchange reactions between
M[N(SiMe3)2]2 (M = Ge, Sn) and the pyridine-containing dialcohol
ligands afford compounds 1–6 in moderate to good yields. The
structures of closely related dimeric stannylene 4 and monomeric
germylene 5 were studied by X-ray diffraction analysis. Stannyl-
enes 4 and 6 were found to be dimeric in solution according to
119Sn NMR spectroscopy data. The mentioned above ligands and
related compounds are promising for discriminative synthesis of
monomeric and dimeric stannylenes/germylenes. Further studies
on chemical behaviour of these novel class of ‘‘heavier” carbenes
are in progress.
In order to get an additional evidence supporting the structure
of insoluble stannylene 2, we carried out the reaction of 2 with
molecular bromine. This reaction as well as analogous reactions
of 1 and 3 with Br2 led to the expected derivatives of virtually pen-
tacoordinated germanium and tin 7–9 (Scheme 1).
Thus, we can conclude that compounds 1–6 are ‘‘heavier” carb-
enes and they exist as monomers or coordination oligomers (obvi-
Z
N
Z
CR2 OH
CR'2 OH
Z CR2 O
N
[(Me3Si)2N]2M
- 2 (Me3Si)2NH
M
R'
Z CR'2 O
1-6
M
1 Ge
2 Sn
Z R R'
-
-
M
Z
R
R'
Ge CH2 Ph Ph
Sn CH2 Ph Ph 6 Sn CH2 Ph Me
M
Z
R
Ph Ph
Ph Ph
3
4
5 Ge CH2 Ph Me
Z
N
Z
CR2 O
M
7 Ge
8 Sn
Z
-
-
R
Ph
Ph
Br
Br
Br2
1-3
M
9 Ge CH2 Ph
CR2 O
7-9
Scheme 1. Preparation of complexes 1–9.

3830
M. Huang et al. / Journal of Organometallic Chemistry 694 (2009) 3828–3832
Fig. 1. Molecular structure of 4. Hydrogen atoms are omitted for clarity.
THF-d8 at 295 K). Chemical shifts in the 1H and 13C NMR spectra
3. Experimental
are given in ppm relative to internal Me4Si. Elemental analyses
were carried out by the Microanalytical Laboratory of the Chemis-
try Department of the Moscow State University.
All manipulations were performed under a dry, oxygen-free
argon atmosphere using standard Schlenk techniques. Ge[N
(SiMe3)2]2 [16], Sn[N(SiMe3)2]2 [16], Py(CPh2OH)2 [17], Py(CH2C-
Me2OH)(CH2CPh2OH) [18] and Py(CH2CPh2OH)2 [19] were syn-
thesised according to the literature procedures. 1H NMR
(400 MHz), 13C NMR (100 MHz) and 119Sn NMR (149 MHz) spectra
were recorded with a Bruker 400 spectrometer (in CDCl3, C6D6 and
3.1. Synthesis of Py(CPh2O)2Ge (1)
A solution of Py(CPh2OH)2 (0.71 g, 1.6 mmol) in toluene (10 ml)
was added to
a stirred solution of [(Me3Si)2N]2Ge (0.61 g,
1.6 mmol) in toluene (10 ml), and the mixture was stirred at room
temperature. After 4 days the solid was filtered off to give 1 as a
yellow solid. Yield 0.45 g (55%). 1H NMR (400 MHz, THF-d8,
ppm): d = 7.19–7.31 (m, 8H), 7.36–7.42 (m, 12H) (aromatic hydro-
gens), 7.91 (d, J = 7.67 Hz, 2H, Hb–C5H3N), 8.28 (t, J = 7.67 Hz, 1H,
H –C5H3N). 13C NMR (100 MHz, THF-d8, ppm): d = 84.74 (CPh2),
c
124.71, 128.50, 128.53, 128.82, 144.35, 145.54, 156.27 (aromatic
carbons and C5H3N groups). Anal. Calc. for C31H23NO2Ge
(514.1299): C, 72.42; H, 4.51; N, 2.72. Found: C, 72.54; H, 4.52;
N, 2.71%.
Table 1
Selected bond lengths (Å) and angles (degrees) in 4 and 5.
4
Sn(1)–O(3)
Sn(1)–O(4)
Sn(1)–O(2)
Sn(1)–N(2)
Sn(2)–O(1)
Sn(2)–O(2)
Sn(2)–O(4)
Sn(2)–N(1)
O(3)–Sn(1)–O(4)
O(3)–Sn(1)–O(2)
2.058(3)
2.183(3)
2.355(3)
2.503(4)
2.064(3)
2.182(3)
2.301(3)
2.494(4)
103.5(1)
87.6(1)
O(4)–Sn(1)–O(2)
O(3)–Sn(1)–N(2)
O(4)–Sn(1)–N(2)
O(2)–Sn(1)–N(2)
O(1)–Sn(2)–O(2)
O(1)–Sn(2)–O(4)
O(2)–Sn(2)–O(4)
O(1)–Sn(2)–N(1)
O(2)–Sn(2)–N(1)
O(4)–Sn(2)–N(1)
69.6(1)
78.0(1)
79.8(1)
142.1(1)
101.8(1)
85.6(1)
70.6(1)
78.4(1)
80.3(1)
143.1(1)
5
Ge(1)–O(1)
Ge(1)–O(2)
Ge(1)–N(1)
1.827(1)
1.881(1)
2.110(1)
O(1)–Ge(1)–O(2)
O(1)–Ge(1)–N(1)
O(2)–Ge(1)–N(1)
97.24(5)
92.67(5)
83.63(5)
Fig. 2. Molecular structure of 5.

M. Huang et al. / Journal of Organometallic Chemistry 694 (2009) 3828–3832
3831
3.2. Synthesis of Py(CPh2O)2Sn (2)
by filtration to give 6 as a white solid. Yield 0.19 g (31%). 1H
NMR (400 MHz C6D6, ppm): d = 0.98, 1.70 (2s, 6H, 2CH3), 2.21,
3.19, (2d, J = 13.90 Hz, 2H, CH2CMe2), 3.42, 3.96 (2d, J = 12.64 Hz,
2H, CH2CPh2), 6.14, 6.23 (2d, J = 7.32 Hz, 2H, Hb–C5H3N), 6.67 (t,
Analogously to 1, complex 2 was prepared from Py(CPh2OH)2
(0.44 g, 1.0 mmol) and [(Me3Si)2N]2Sn (0.45 g, 1.0 mmol) in tolu-
ene (20 mL). The product was isolated by filtration to give 2 as a
white solid. Yield 0.38 g (67%). NMR spectra were not recorded
due to insolubility of 2. Anal. Calc. for C31H23NO2Sn (560.2299):
C, 66.46; H, 4.14; N, 2.50. Found: C, 66.52; H, 4.15; N, 2.49%.
J = 7.32 Hz, 1H, H –C5H3N), 7.10–7.12, 7.17–7.19, 7.26–7.30,
c
7.57–7.60 (4m, 10H, aromatic hydrogens). 13C NMR (100 MHz,
C6D6, ppm): d = 29.86, 33.94 (2CH3), 47.72 (CH2CMe2), 51.34
(CH2CPh2), 74.63 (CMe2), 80.24 (CPh2), 121.91, 123.17, 126.09,
126.85, 127.10, 127.91, 136.89, 148.45, 148.20, 151.45, 153.02,
157.05, 157.67 (aromatic carbons and C5H3N groups). 119Sn NMR
(149 MHz, THF-d8, ppm): d = ꢀ443.62 (br s). Anal. Calc. for
C23H23SnNO2 (464.1443): C, 59.52; H, 4.99; N, 3.02. Found: C,
59.44; H, 4.98; N, 3.01%.
3.3. Synthesis of Py(CH2CPh2O)2Ge (3)
Analogously to 1, complex 3 was prepared from Py(CH2C-
Ph2OH)2 (0.79 g, 1.7 mmol) and [(Me3Si)2N]2Ge (0.66 g, 1.7 mmol)
in toluene (20 mL). The product was isolated by filtration to give
3 as a white solid. Yield 0.67 g (74%). 1H NMR (400 MHz, THF-d8,
ppm): d = 3.63, 4.13 (2d, J = 13.8 Hz, 4H, 2 CH2), 6.67–6.97, 7.05–
7.10, 7.27–7.37, 7.39–7.44, 7.72–7.78 (5m, 20H, aromatic hydro-
gens), 7.01 (d, J = 7.89 Hz, 2H, Hb–C5H3N), 7.52 (t, J = 7.89 Hz, 1H,
3.7. Reaction of Py(CH2OH)2 with [(Me3Si)2N]2Ge
A solution of Py(CH2OH)2 (0.18 g, 1.3 mmol) in toluene (10 ml)
was added to
a stirred solution of [(Me3Si)2N]2Ge (0.52 g,
H –C5H3N). 13C NMR (100 MHz THF-d8, ppm): d = 47.17 (CH2),
1.3 mmol) in toluene (10 ml), and the mixture was stirred at room
temperature. After 4 days a yellow solid was filtered to give 0.21 g
(77%) of ‘‘Py(CH2O)2Ge‘‘. NMR spectra were not recorded due to
insolubility of ‘‘Py(CH2O)2Ge‘‘. Anal. Calc. for C7H7GeNO2
(209.746): C, 40.08; H, 3.36; N, 6.68. Found: C, 40.11; H, 3.37; N,
6.66%.
c
77.72 (CPh2), 126.15, 126.87, 127.12, 127.20, 127.41, 127.88,
128.30, 128.41, 140.45, 149.85, 155.88 (aromatic carbons and
C5H3N groups). Anal. Calc. for C33H27GeNO2 (542.183): C, 73.10;
H, 5.02; N, 2.58. Found: C, 73.35; H, 5.03; N, 2.59%.
3.4. Synthesis of Py(CH2CPh2O)2Sn (4)
3.8. Synthesis of Py(CPh2O)2GeBr2 (7)
A solution of Py(CH2CPh2OH)2 (0.53 g, 1.1 mmol) in toluene
(10 ml) was added to a stirred solution of [(Me3Si)2N]2Sn (0.50 g,
1.1 mmol) in toluene (10 ml), and the mixture was stirred at room
temperature. After 4 days all volatiles were removed under re-
duced pressure. Then ether (20 ml) was added to the residue, the
precipitate was filtered to give 4 as a white powder. Yield 0.52 g
(51%). 1H NMR (400 MHz, C6D6, ppm): d = 3.14, 3.68 (2d,
J = 12.50 Hz, 4H, 2 CH2), 5.83 (d, J = 7.83 Hz, 2H, Hb–C5H3N), 6.29
To a stirred solution of 1 (0.23 g, 0.4 mmol) in THF (10 ml) a
solution of Br2 (0.07 g, 0.4 mmol) was added dropwise at room
temperature. After 7 days all volatiles were removed under re-
duced pressure. Then ether (20 ml) was added to the residue, the
precipitate was filtered to give 7 as a white powder. Yield 0.12 g
(41%). 1H NMR (400 MHz, CDCl3, ppm): d = 7.20–7.30, 7.31–7.36
(2m, 20H, aromatic hydrogens), 7.61 (d, J = 7.58 Hz, 2H, Hb–
(t, J = 7.83 Hz, 1H, H –C5H3N), 6.87–6.97, 6.98–7.10, 7.25–7.40,
C5H3N), 8.07 (t, J = 7.58 Hz, 1H, H –C5H3N). 13C NMR (100 MHz,
c
c
7.62–7.75 (4m, 20H, aromatic hydrogens). 13C NMR (100 MHz,
C6D6, ppm): d = 48.82 (CH2), 80.47 (CPh2), 122.67, 125.61, 125.64,
126.49, 126.71, 126.76, 127.33, 128.51, 129.27, 136.75, 156.22
(aromatic carbons and C5H3N groups). 119Sn NMR (149 MHz,
C6D6, ppm): d = ꢀ485.89 (br s). Anal. Calc. for C33H27NO2Sn
(588.283): C, 67.37; H, 4.63; N, 2.38. Found: C, 67.45; H, 4.62, N,
2.38%.
CDCl3, ppm): d = 83.94 (CPh2), 123.34, 127.62, 128.05, 128.27,
142.58, 143.83, 155.84 (aromatic carbons and C5H3N groups). Anal.
Calc. for C31H23Br2GeNO2 (673.9379): C, 55.25; H, 3.44; N, 2.08.
Found: C, 55.24; H, 3.43; N, 2.08%.
3.9. Synthesis Py(CPh2O)2SnBr2 (8)
Analogously to 7, complex 8 was prepared from 2 (0.12 g,
0.2 mmol) and a solution of Br2 (0.04 g, 0.2 mmol) in THF (10 ml).
The product was isolated by filtration to give 8 as a white solid.
Yield 0.13 g (87%). 1H NMR (400 MHz, CDCl3, ppm): d = 7.26–7.38
(m, 20H, aromatic hydrogens), 7.59 (d, J = 7.83 Hz, 2H, Hb–
3.5. Synthesis of Py(CH2CPh2O)(CH2CMe2O)Ge (5)
Analogously to 4, complex 5 was prepared from Py(CH2C-
Ph2OH)(CH2CMe2OH) (0.38 g, 1.1 mmol) and [(Me3Si)2N]2Ge
(0.43 g, 1.1 mmol) in toluene (20 mL). The product was isolated
by filtration to give 5 as a white solid. Yield 0.17 g (34%). 1H
NMR (400 MHz, C6D6, ppm): d = 0.90, 1.59 (2s, 6H, 2 CH3), 2.32,
2.83 (2d, J = 14.15 Hz, 2H, 2 CH2), 3.54 (s, 2H, CH2CPh2); 6.19 (t,
C5H3N), 8.04 (t, J = 7.83 Hz, 1H, H –C5H3N). 13C NMR (100 MHz,
c
CDCl3, ppm): d = 82.32 (CPh2); 123.84, 127.85, 127.88, 128.22,
141.62, 145.34, 158.37 (aromatic carbons and C5H3N groups). Anal.
Calc. for C31H23Br2NO2Sn (720.0379): C, 51.71; H, 3.22; N, 1.95.
Found: C, 51.60; H, 3.23; N, 1.95%.
J = 7.32 Hz, 2H, Hb–C5H3N), 6.63 (t, J = 7.32 Hz, 1H, H –C5H3N),
c
6.81–6.86, 6.95–7.03, 7.10–7.13, 7.20–7.25, 7.54–7.58, 7.77–7.82
(6m, 10H, aromatic hydrogens). 13C NMR (100 MHz, C6D6, ppm):
d = 30.10, 34.06 (2CH3), 47.17 (CH2CMe2), 47.83 (CH2CPh2), 69.08
(CMe2), 77.34 (CPh2), 123.18, 124.06, 126.70, 127.11, 127.44,
127.88, 128.51, 1289.28, 138.78, 149.16, 151.09, 155.81, 156.43
(aromatic carbons and C5H3N groups). Anal. Calc. for C23H23GeNO2
(418.0443): C, 66.08; H, 5.55; N, 3.35. Found: C, 65.98; H, 5.53; N,
3.36.
3.10. Synthesis Py(CH2CPh2O)2GeBr2 (9)
Analogously to 7, complex 9 was prepared from 3 (0.21 g,
0.4 mmol) and a solution of Br2 (0.07 g, 0.4 mmol) in THF (10 ml).
The product was isolated by filtration to give 9 as a white solid.
Yield 0.16 g (59%). 1H NMR (400 MHz, CDCl3, ppm): d = 4.29 (s,
4H, CH2), 6.48 (d, J = 7.58 Hz, 2H, Hb–C5H3N), 7.19–7.24, 7.26–
7.31, 7.37–7.44 (3m, 21H, aromatic hydrogens and H –C5H3N
c
3.6. Synthesis of Py(CH2CPh2O)(CH2CMe2O)Sn (6)
groups). 13C NMR (100 MHz, CDCl3, ppm): d = 43.52 (CH2); 84.43
(CPh2); 125.94, 126.10, 128.10, 128.22, 140.02, 144.92, 155.12
(aromatic carbons and C5H3N groups). Anal. Calc. for C33H27Br2Ge-
NO2 (701.991): C, 56.46; H, 3.88; N, 2.00. Found: C, 56.38; H, 3.89;
N, 2.00%.
Analogously to 4, complex 6 was prepared from Py(CH2C-
Ph2OH)(CH2CMe2OH) (0.45 g, 1.3 mmol) and [(Me3Si)2N]2Sn
(0.57 g, 1.3 mmol) in toluene (20 mL). The product was isolated

3832
M. Huang et al. / Journal of Organometallic Chemistry 694 (2009) 3828–3832
Table 2
References
Details of crystallographic experiments for 4 and 5.
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Formula
Fw
Crystal system
Space group, Z
a (Å)
C80H70N2O4Sn2
1360.76
monoclinic
P21/c 4
16.974(2)
16.2324(19)
22.966(3)
95.498(2)
6288.8(13)
1.437
C23H23N1O2Ge1
418.01
monoclinic
P21/n 4
10.4147(3)
13.1728(4)
14.1632(5)
100.757(1)
1908.92(10)
1.454
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dcalc (g cmꢀ3
)
Abs coeff. (mmꢀ1
F(0 0 0)
)
0.849
2784
1.623
864
´
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h Range (°)
1.74–27.00
56 811
13 660 (0.0902)
13 660/795
0.0595/0.1580
2.192/ꢀ1.624
2.13–28.00
19 321
4607 (0.0247)
4607/336
0.0252/0.0694
0.441/ꢀ0.216
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R1 [I > 2
r(I)]/wR2 (all data)
Largest difference in peak/hole (e Åꢀ3
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3.11. Reaction of ‘‘Py(CH2O)2Ge‘‘ with Br2
To a stirred solution of ‘‘Py(CH2O)2Ge‘‘ (0.09 g, 0.4 mmol) in THF
(10 ml) a solution of Br2 (0.07 g, 0.4 mmol) was added dropwise at
room temperature. After 7 days all volatiles were removed under
reduced pressure. Then ether (20 ml) was added to the residue,
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3.12. X-ray crystallographic study
Experimental details are given in Table 2. The data were col-
lected on a Bruker SMART APEX II diffractometer using Mo Ka radi-
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anisotropic thermal parameters for all non-hydrogen atoms
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(
SHELXTL-Plus). In 5, all hydrogen atoms were found from difference
Fourier syntheses and refined isotropically. As for 4, all hydrogen
atoms were placed in calculated positions and refined using a
riding model [20].
(e) A.V. Churakov, S.S. Karlov, E. Kh. Yakubova, A.A. Selina, M.V. Zabalov, Y.F.
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Supplementary material
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(2000) 2735.
CCDC 717017 and 717018 contain the supplementary crystallo-
graphic data for complexes 4 and 5. These data can be obtained
free of charge from The Cambridge Crystallographic Data Centre
via www.ccdc.cam.ac.uk/data_request/cif.
Acknowledgements
[20] SHELXTL-Plus. Release 6.10. Bruker AXS Inc., Madison, Wisconsin, USA, 2000.
The authors thank Russian Foundation for Basic Research (Grant
09-03-00536-a) and Presidium RAS program.