Synthesis of chalcogeno[3-(pyrid-2-yl)-1-azaallyl]germanium complexes

Article abstract of DOI:10.1002/ejic.200500717

The reaction of [Ge{C(C₅H₄N-2)C(Ph)N(SiMe ₃)₂}{N(SiMe₃)C(Ph)C(SiMe₃)(C ₅H₄N-2)}] (1) and [Ge{N(SiMe₃)C(Ph)C(SiMe ₃)(C₅H₄N-2

Full text of DOI:10.1002/ejic.200500717

FULL PAPER
DOI: 10.1002/ejic.200500717
Synthesis of Chalcogeno[3-(pyrid-2-yl)-1-azaallyl]germanium Complexes
Wing-Por Leung,*[a] Kim-Hung Chong,[a] Yuen-Sze Wu,[a] Cheuk-Wai So,[a]
Hoi-Shan Chan,[a] and Thomas C. W. Mak[a]
Keywords: Chalcogens / Germanium / N ligands
The reaction of [Ge{C(C5H4N-2)C(Ph)N(SiMe3)2}{N(SiMe3)-
C(Ph)C(SiMe3)(C5H4N-2)}] (1) and [Ge{N(SiMe3)C(Ph)-
C(SiMe3)(C5H4N-2)}Cl] (2) with stoichiometric amounts of el-
emental chalcogens in toluene affords [Ge(E){C(C5H4N-2)-
C(Ph)N(SiMe3)2}{N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}] [E = S
(3), Se (4)] and [Ge(E){N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}Cl]
[E = S (5), Se (6)], respectively. Compounds 3–6 were charac-
terized by X-ray analysis.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2006)
metric amount of elemental chalcogen in toluene afforded
the thermally stable germanethione 3 and -selone 4
(Scheme 1). Similarly, treatment of [Ge{N(SiMe3)C(Ph)-
C(SiMe3)(C5H4N-2)}Cl] (2) with an equimolar amount of
elemental chalcogen in toluene gave the thermally stable
complexes [Ge(E){N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}Cl]
[E = S (5), Se (6)] (Scheme 2).
Introduction
Compounds containing a double bond between group 14
and 16 elements are considered to be unstable due to the
weak pπ–pπ bonding.[1] Nevertheless, stable chalcogenoger-
mane and -stannane (ϾM=E) (M = Ge, Sn; E = S, Se, Te)
complexes have been isolated in the past few years.[2] These
compounds are either base-stabilized or stabilized by steri-
cally bulky protecting group. For example, [{η4-
Me8taa}M=E] (M = Ge, Sn; E = S, Se; η4-Me8taa = octa-
methyldibenzotetraaza[14]annulene),[3] [(Tbt)(Tip)Ge=E]
{Tbt = 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl; Tip =
2,4,6-triisopropylphenyl; E = S, Se, Te},[4] and [RN2M=E]
[RN = CPh(SiMe3)C5H4N-2; M = Ge; E = S, Se, Te; RN
=
CH(SiMe3)C9H6N-8; M = Sn; E = S, Se, Te][5] have been
reported. In contrast, chalcogeno group 14 metal halide
complexes [RM(E)X] are rare, and to date only the com-
plexes [{HC(CMeNAr)2}Ge(E)X] (Ar = 2,6-iPr2C6H3, Ph;
E = S, Se; X = F, Cl) have been prepared and structurally
characterized.[6]
Scheme 1.
Recently, we have reported the synthesis of
[Ge{C(C5H4N-2)C(Ph)N(SiMe3)2}{N(SiMe3)C(Ph)C(SiMe3)-
(C5H4N-2)}] and [Ge{N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}-
Cl] from the reaction of GeCl2·dioxane with the [3-(pyrid-
2-yl)-1-azaallyl]lithium complex [Li{N(SiMe3)C(Ph)C(R)-
(C5H4N-2)}]2.[7] Herein, we report the synthesis of chalco-
genogermanium complexes from the direct reaction of these
complexes with elemental chalcogens.
Scheme 2.
Compounds 3–6 are yellow, crystalline solids that are sol-
uble in Et2O, toluene, and THF and sparingly soluble in
Results and Discussion
The reaction of [Ge{C(C5H4N-2)C(Ph)N(SiMe3)2}- hydrocarbon solvents. The 13C NMR spectra of 3 and 4
{N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}] (1) with a stoichio- display three sharp singlets assignable to the three types of
SiMe3 groups, consistent with the solid-state structure. The
1H and 13C NMR spectra of 5 and 6 show a similar pattern
and display one set of signals due to the 3-(pyrid-2-yl)-1-
azaallyl ligand.
[a] Department of Chemistry, The Chinese University of Hong
Kong,
Shatin, New Territories, Hong Kong, China
E-mail: kevinleung@cuhk.edu.hk
808
© 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2006, 808–812

Chalcogeno[3-(pyrid-2-yl)-1-azaallyl]germanium Complexes
FULL PAPER
The 77Se NMR spectrum of 4 displays a singlet at δ =
–28.63 ppm, whereas the 77Se NMR spectrum of 6 displays
a singlet at δ = –266.21 ppm, which is similar to that found
for [{HC(CMeNAr)2}Ge(Se)Cl] (Ar = 2,6-iPr2C6H3; δ =
–228 ppm). The values for 4 and 6 lie between those
of [Ge{(NSiMe3)2}2(µ-Se)]2 (δ
=
–476.0 ppm)[8] and
[(Tbt)(Tip)Ge=Se] (δ = 940 ppm).[4b] We suggest that 4 and
6 exist as intermediates between the resonance forms A and
B in solution (Scheme 3).
Scheme 3.
The molecular structures, with the atom-numbering
schemes, of compounds 3 and 6 are shown in Figures 1 and
2, respectively. Selected bond lengths and angles of com-
plexes 3/4 and 5/6 are listed in Tables 1 and 2, respectively.
Compounds 3 and 4 are isostructural. The germanium
center is bonded to an [2-(pyrid-2-yl)ethenyl]amido-N,NЈ
chelate and an η1-alkenyl ligand in a tetrahedral geometry,
with the chalcogen atom occupying the axial position.
Compounds 5 and 6 are also isostructural, and the geome-
try around the germanium center is also tetrahedral.
Figure 2. Molecular structure of 6.
The Ge–S distance of 2.094(8) Å in 3 is similar to that
of 2.11 Å in [{η4-Me8taa}Ge=S][3a] and 2.063(3) Å in
The Ge–Se distance of 2.223(9) Å in 4 is similar to that
[(Tbt)(Tip)Ge=S],[4a] and the Ge–S distance of 2.056(2) Å of 2.247(7) Å in [{C(SiMe3)2C5H4N-2}2Ge=Se][10] and
in 5 is comparable to that of 2.053(6) Å in [{HC(CMe- 2.247(1) Å in [{η4-Me8taa}Ge=Se],[3a] and the Ge–Se dis-
NAr)2}Ge(S)Cl] (Ar = 2,6-iPr2C6H3).[6a] The Ge–S dis- tance of 2.191(1) Å in 6 is comparable to that of 2.210(1) Å
tances in 3 and 5 are close to the calculated value for a in [{HC(CMeNPh)2}Ge(Se)Cl].[6b] The Ge–Se bond length
Ge=S bond (2.06 Å).[9] This suggests that the resonance in 4 lies between the calculated values for a Ge–Se single
structure A contributes more than the resonance B (2.39 Å) and double bond (2.19 Å), suggesting that the type
(Scheme 3) in compounds 3 and 5.
of Ge–Se bonding in 4 lies somewhere between the reso-
Figure 1. Molecular structure of 3.
Eur. J. Inorg. Chem. 2006, 808–812
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809

W.-P. Leung, K.-H. Chong, Y.-S. Wu, C.-W. So, H.-S. Chan, T. C. W. Mak
FULL PAPER
Table 1. Selected bond lengths [Å] and angles [°] for compounds 3
and 4.
The Ge–Cl distances of 2.180(2) Å in 5 and 2.179(2) Å
in 6 are shorter than that of 2.283(9) Å in 2. Similarly, the
Ge–Namide distances [1.878(17) (3), 1.873(3) (4), 1.840(4)
(5), 1.823(5) Å (6)] are shorter than those in the corre-
sponding parent complexes [1.942(17) (1), 1.920(2) Å (2)].[7]
This is because the germanium center in 3–6 has a higher
oxidation state.
3
Ge–S
Ge–N(1)
C(25)–C(26)
N(4)–Si(4)
C(12)–C(25)
N(1)–C(1)
2.094(8)
1.999(17) Ge–C(25)
1.349(3) N(4)–C(26)
1.768(18) Si(3)–N(4)
Ge–N(2)
1.878(17)
1.969(19)
1.435(2)
1.764(18)
1.498(3)
1.466(3)
1.388(3)
1.778(7)
89.0(7)
121.2(6)
106.9(6)
121.2(2)
114.3(2)
119.0(2)
1.482(3)
1.357(3)
1.382(3)
1.902(2)
108.4(8)
109.1(8)
117.8(6)
118.8(1)
124.3(2)
124.3(2)
C(17)–C(26)
C(1)–C(23)
N(2)–C(24)
Si(2)–N(2)
N(2)–Ge–N(1)
N(2)–Ge–S
C(23)–C(24)
Si(1)–C(23)
Conclusions
N(2)–Ge–C(25)
C(25)–Ge–N(1)
C(25)–Ge–S
C(1)–N(1)–Ge
C(24)–C(23)–C(1)
C(25)–C(26)–N(4)
A series of chalcogeno[2-(pyrid-2-yl)-1-azaallyl]germa-
nium complexes has been synthesized, namely [Ge(E)-
{C(C5H4N-2)C(Ph)N(SiMe3)2}{N(SiMe3)C(Ph)C(SiMe3)-
(C5H4N-2)}] [E = S (3), Se (4)] and [Ge(E){N(SiMe3)C(Ph)-
C(SiMe3)(C5H4N-2)}Cl] [E = S (5), Se (6)]. The Ge–E bond
lengths in compounds 3–6 are indicative of a formal double
bond or a Ge–E σ-bond with significant ionic charac-
ter.[6a,6b]
N(1)–Ge–S
N(1)–C(1)–C(23)
N(4)–C(26)–C(17)
C(26)–N(4)–Si(3)
4
Ge–Se
Ge–N(1)
N(2)–C(26)
C(5)–C(25)
C(18)–C(23)
C(12)–C(24)
Si(2)–N(4)
2.223(9)
1.996(3)
1.402(6)
1.465(7)
1.502(5)
1.490(6)
1.757(4)
1.762(4)
1.490(6)
109.7(2)
Ge–N(2)
Ge–C(23)
1.873(3)
1.976(4)
1.399(6)
1.365(6)
1.345(5)
1.441(4)
1.767(3)
1.894(5)
C(25)–C(26)
N(1)–C(5)
C(23)–C(24)
N(4)–C(24)
Si(1)–N(4)
Si(4)–C(25)
Experimental Section
General Remarks: All manipulations were carried out under dini-
trogen by standard Schlenk techniques. Solvents were dried with,
and distilled from, CaH2 (hexane) and/or Na (Et2O, toluene and
THF). Anhydrous S and Se were purchased from Aldrich Chemi-
cals and used without further purification. [Ge{C(C5H4N-2)C(Ph)-
Si(3)–N(2)
C(6)–C(26)
N(2)–Ge–C(23)
C(23)–Ge–N(1)
C(23)–Ge–Se
C(18)–C(23)–Ge
N(2)–Ge–N(1)
88.9(1)
120.6(1)
108.0(1)
109.0 (2) N(2)–Ge–Se
116.6(1)
111.4(3)
N(1)–Ge–Se
C(24)–C(23)–C(18) 124.1(3)
N(SiMe3)2}{N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}]
(1)
and
C(23)–C(24)–C(12) 120.5(3)
N(4)–C(24)–C(12)
Si(2)–N(4)–Si(1)
C(26)–N(2)–Ge
Si(3)–N(2)–Ge
C(25)–C(26)–N(2)
N(1)–C(5)–C(25)
114.9(3)
122.1(2)
113.3(3)
121.8(2)
125.2(4)
120.6(4)
[Ge{N(SiMe3)C(Ph)C(SiMe3)-(C5H4N-2)}Cl] (2) were prepared ac-
cording to literature procedures.[7] The 1H, 13C, and 77Se NMR
spectra were recorded with Bruker WM-300 or Varian 400 instru-
ments. All spectra were recorded in [D8]THF, and the chemical
shifts are given relative to SiMe4 (1H, 13C) or Se2Me2 (77Se).
C(24)–N(4)–Si(1)
C(24)–C(23)–Ge
C(26)–N(2)–Si(3)
C(25)–C(26)–C(6)
C(26)–C(25)–C(5)
118.3(3)
122.3(3)
122.8(2)
118.5(4)
117.6(4)
[{N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}{C(C5H4N-2)C(Ph)N(Si-
Me3)2}Ge=S] (3): A solution of 1 (0.73 g, 0.97 mmol) in toluene
(30 mL) was added slowly to a suspension of sulfur (0.03 g,
0.97 mmol) in toluene (25 mL) at 0 °C. The yellow mixture was
warmed to room temperature and stirred at room temperature for
16 h. The precipitate was filtered and the filtrate was concentrated
to yield yellow crystals of 3. Yield: 0.23 g (30%); m.p. 222–226 °C
(dec.). C38H54GeN4SSi4 (783.9): calcd. C 58.22, H 6.94, N 7.14;
found C 58.12, H 7.03, N 7.29. 1H NMR (300 MHz, [D8]THF,
25 °C): δ = –0.40 (s, SiMe3, 9 H), –0.12 (s, SiMe3, 9 H), –0.06 (s,
SiMe3, 9 H), –0.03 (s, SiMe3, 9 H), 6.70 (t, J = 6.5 Hz, py, 1 H),
7.21–7.32 (m, Ph, 5 H), 7.34–7.37 (m, py, 1 H), 7.40–7.47 (m, Ph,
5 H), 7.61–7.65 (m, py, 1 H), 7.77–7.79 (m, py, 1 H), 8.35 (d, J =
5.7 Hz, py, 1 H), 8.47 (d, J = 4.5 Hz, py, 1 H), 8.53 (d, J = 4.8 Hz,
py, 1 H), 8.78 (d, J = 6 Hz, py, 1 H) ppm. 13C{1H} NMR
(300 MHz, [D8]THF, 25 °C): δ = 1.76, 2.23, 2.76 (SiMe3), 94.46
(CSiMe3), 111.70, 119.02, 125.05, 128.49, 130.81, 132.08, 133.10,
134.44, 137.29, 140.76, 143.45, 145.18, 146.21, 147.81, 151.83,
157.03, 160.04, 162.42 (Ph and py), 163.95 (pyCGe), 164.26, 165.64
(NCPh) ppm.
Table 2. Selected bond lengths [Å] and angles [°] for compounds 5
and 6.
[Ge(E){N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}Cl]
E = S (5)
E = Se (6)
Ge(1)–E(1)
Ge(1)–Cl(1)
Ge(1)–N(2)
N(2)–C(10)
C(6)–C(10)
C(5)–C(6)
C(5)–N(1)
N(1)–Ge(1)
N(1)–Ge(1)–N(2)
E(1)–Ge(1)–Cl(1)
N(2)–Ge(1)–E(1)
N(2)–Ge(1)–Cl(1)
Ge(1)–N(2)–C(10)
N(2)–C(10)–C(6)
C(10)–C(6)–C(5)
C(5)–N(1)–Ge(1)
N(1)–Ge(1)–Cl(1)
N(1)–Ge(1)–E(1)
2.056(2)
2.180(2)
1.840(4)
1.392(6)
1.388(7)
1.475(8)
1.345(7)
1.952(5)
94.0(2)
116.1(8)
124.5(1)
103.5(2)
113.3(3)
124.5(5)
120.0(5)
119.0(4)
99.2(2)
2.191(1)
2.179(2)
1.823(5)
1.410(7)
1.362(7)
1.465(7)
1.357(8)
1.947(5)
94.5(2)
116.1(8)
125.8(1)
103.1(2)
112.9(3)
124.2(5)
120.1(5)
117.9(3)
99.7(2)
[{N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}{C(C5H4N-2)C(Ph)N(Si-
Me3)2}Ge=Se] (4): A solution of 1 (0.75 g, 1.00 mmol) in toluene
(15 mL) was added to a stirred suspension of selenium powder
(0.08 g, 1.00 mmol) in toluene (15 mL) at 0 °C. The resultant yel-
lowish-orange solution was warmed to room temperature and
stirred for 18 h. Unreacted selenium powder was removed by fil-
tration. The filtrate was concentrated and stored at –30 °C. Com-
pound 4 was obtained as yellow crystals. Yield: 0.50 g (60%); m.p.
114.9(2)
112.9(1)
nance structures A and B. The short Ge–Se distance in 6
indicates a double bond between germanium and selenium
in the solid state.
810
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Eur. J. Inorg. Chem. 2006, 808–812

Chalcogeno[3-(pyrid-2-yl)-1-azaallyl]germanium Complexes
FULL PAPER
Table 3. Crystallographic data for compounds 3–6.
3
4
5
6
Empirical formula
Formula mass
Color
Crystal system
Space group
a [Å]
b [Å]
c [Å]
α [°]
C38H54GeN4SSi4
783.86
yellow
C38H54GeN4Si4Se
832.78
yellow
C19H27ClGeN2SSi2
479.71
yellow
monoclinic
C2/c
33.234(3)
6.5646(3)
21.5209(3)
90
C19H27ClGeN2Si2Se
526.61
yellow
triclinic
triclinic
triclinic
¯
¯
¯
P1
P1
P1
11.290(2)
12.724(3)
15.977(3)
77.49(3)
11.380(2)
12.722(3)
16.049(3)
77.12(3)
6.7285(13)
11.154(2)
16.577(3)
86.17(3)
β [°]
89.89(3)
72.51(3)
2132.1(7)
2
1.221
0.910
828
89.53(3)
72.42(3)
2154.9(7)
2
1.283
1.697
868
90.750(2)
90
4694.8(6)
8
1.357
1.616
88.45(3)
76.08(3)
1204.8(4)
2
1.452
2.998
532
γ [°]
V [Å3]
Z
dcalcd. [gcm–3]
µ [mm–1]
F(000)
1984
Crystal size [mm]
2θ range [°]
Index range
0.48×0.46×0.38
2.13–24.99
–13 Յ h Յ 12
–15 Յ k Յ 0
–18 Յ l Յ 18
7488
0.30×0.21×0.13
1.73–25.00
–13 Յ h Յ 13
–14 Յ k Յ 15
0 Յ l Յ 19
4741
0.50×0.40×0.20
1.23–28.72
–38 Յ h Յ 44
–8 Յ k Յ 8
–27 Յ l Յ 29
16056
0.50×0.40×0.30
1.23–25.60
–7 Յ h Յ 7
–13 Յ k Յ 0
–20 Յ l Յ 19
3778
No. of reflections collected
No. of independent reflections
R1, wR2 [I Ͼ 2σ(I)]
5814
3833
6019
3778
0.0496, 0.1366
0.0739, 0.1495
1.025
0.0771, 0.1983
0.0972, 0.2149
1.067
0.0668, 0.1534
0.1606, 0.2041
0.949
0.0722, 0.1955
0.0771, 0.2043
1.082
R1, wR2 (all data)
Goodness of fit (F2)
No. of data/restraints/parameters
7488/0/434
0.582/–0.703
4741/0/447
0.910/–0.610
6019/0/235
1.169/–0.582
3778/0/235
1.029/–1.399
Largest difference peaks [eÅ–3]
233–236 °C (dec.). C38H54GeN4Si4Se (830.8): calcd. C 54.94, H
6.55, N 6.75; found C 55.07, H 6.63, N 6.94. H NMR (300 MHz,
warmed to room temperature and stirred for 18 h. The precipitate
was filtered and the filtrate was added to 5 mL of CH2Cl2 and
1
[D8]THF, 25 °C): δ = –0.30 (s, SiMe3, 9 H), –0.21 (s, SiMe3, 9 H), concentrated to yield yellow crystals of 5. Yield: 0.35 g (60%); m.p.
–0.17 (s, SiMe3, 9 H), 0.00 (s, SiMe3, 9 H), 6.87–6.90 (m, py, 1 H),
6.91–6.94 (m, py, 1 H), 7.05–7.14 (m, Ph, 5 H), 7.16–7.18 (m, py,
1 H), 7.25–7.27 (m, py, 1 H), 7.33–7.38 (m, Ph, 5 H), 7.48–7.52 (m,
py, 1 H), 7.67 (t, J = 6.9 Hz, py, 1 H), 7.98 (d, J = 4.8 Hz, py, 1
H), 8.27 (d, J = 3.9 Hz, py, 1 H) ppm. 13C{1H} NMR (300 MHz,
[D8]THF, 25 °C): δ = 2.31, 2.77, 2.86 (SiMe3), 114.60 (CSiMe3),
118.94, 119.46, 124.54, 124.69, 127.60, 127.95, 128.33, 129.08,
130.99, 131.59, 135.63, 137.93, 144.30, 145.67, 147.59, 148.31,
198–200 °C. C19H27ClGeN2Si2Se•1/2CH2Cl2 (569.1): calcd. C
41.15, H 4.96, N 4.96; found C 41.41, H 5.17, N 5.17. 1H NMR
(300 MHz, [D8]THF, 25 °C): δ = –0.15 (s, SiMe3, 9 H), –0.01 (s,
SiMe3, 9 H), 7.42–7.52 (m, 1 H, 5-py), 7.58–7.72 (m, 5 H, Ph),
7.75–7.77 (m, 1 H, 3-py), 8.24–8.25 (m, 1 H, 4-py), 9.34–9.36 (m,
1 H, 6-py) ppm. 13C{1H} NMR (300 MHz, [D8]THF, 25 °C): δ =
1.74, 3.47 (SiMe3), 116.47 (CSiMe3), 122.70, 127.50, 128.63, 129.52,
131.48, 132.19, 142.73, 144.83, 157.28 (Ph and py), 164.65 (NCPh)
150.69, 153.95 (Ph and py), 156.32 (pyCGe), 167.06, 171.49 ppm. 77Se NMR (400 MHz, [D8]THF, 25 °C): δ = –266.21 ppm.
(NCPh) ppm. 77Se NMR (400 MHz, [D8]THF, 25 °C): δ =
–28.63 ppm.
X-ray Crystallographic Study: Single crystals were sealed in Linde-
mann glass capillaries under nitrogen. X-ray data of 3–6 were col-
lected with a Rigaku R-AXIS II imaging plate using graphite-mo-
nochromated Mo-Kα radiation (λ = 0.71073 Å) from a rotating-
anode generator operating at 50 kV and 90 mA. Crystal data for
3–6 are summarized in Table 3. The structures were solved by direct
phase determination using the computer program SHELXTL-
PC[11] with a PC 486 and refined by full-matrix least-squares with
anisotropic thermal parameters for the non-hydrogen atoms. Hy-
drogen atoms were introduced in their idealized positions and in-
cluded in structure factor calculations with assigned isotropic
temperature factor calculations. CCDC-292827 (3), -292825 (4)
-292826 (5), and -292824 (6) contain the supplementary crystallo-
graphic data for this paper. These data can be obtained free of
charge from The Cambridge Crystallographic Data Center via
www.ccdc.cam.ac.uk/data_request/cif.
[Ge(S){N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}Cl] (5): A solution of
2 (0.48 g, 1.07 mmol) in toluene (15 mL) was added to a stirred
suspension of sulfur powder (0.035 g, 1.09 mmol) in toluene
(15 mL) at 0 °C. The resultant yellowish-orange solution was
warmed to room temperature and stirred for 18 h. The precipitate
was filtered and the filtrate was concentrated to yield yellow crys-
tals of 5. Yield: 0.28 g (54%); m.p. 250–252 °C. C19H27ClGeN2SSi2
(479.7): calcd. C 47.63, H 5.68, N 5.85; found C 47.36, H 5.10, N
5.85. 1H NMR (300 MHz, [D8]THF, 25 °C): δ = –0.14 (s, SiMe3, 9
H), 0.00 (s, SiMe3, 9 H), 7.42–7.49 (m, 1 H, 5-py), 7.49–7.69 (m, 5
H, Ph), 7.75–7.78 (m, 1 H, 3-py), 8.25–8.26 (m, 1 H, 4-py), 9.26–
9.28 (m, 1 H, 6-py) ppm. 13C{1H} NMR (300 MHz, [D8]THF,
25 °C): δ = 1.80, 3.11 (SiMe3), 116.01 (CSiMe3), 123.73, 128.65,
129.46, 131.48, 131.89, 132.14, 142.11, 144.80, 157.63 (Ph and py),
164.83 (NCPh) ppm.
[Ge(Se){N(SiMe3)C(Ph)C(SiMe3)(C5H4N-2)}Cl] (6): A solution of
2 (0.50 g, 1.12 mmol) in toluene (15 mL) was added to a stirred
suspension of selenium powder (0.089 g, 1.13 mmol) in toluene
(15 mL) at 0 °C. The resultant yellowish-orange solution was
Acknowledgments
This work was supported by the Hong Kong Research Grants
Council (project no. CUHK 4265-00P).
Eur. J. Inorg. Chem. 2006, 808–812
© 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
811

W.-P. Leung, K.-H. Chong, Y.-S. Wu, C.-W. So, H.-S. Chan, T. C. W. Mak
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Received: August 11, 2005
Published Online: December 27, 2005
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