Article
Organometallics, Vol. 28, No. 20, 2009 6019
for 1.5 h at 90 °C. Removal of the solvent under reduced
pressure and washing the resulting pale yellow solid with hexane
(3 ꢁ 3 mL) yielded 2 (366 mg, 87%). Recrystallization from
hexane/toluene (3:1) at rt gave yellow crystals of 2 suitable for
X-ray crystallography. Anal. Calcd for C42H46Ge3P2Pt: C, 49.18;
H, 4.52. Found: C, 48.39; H, 4.31. 1H NMR (300 MHz, C6D6,
rt): δ 7.79 (dd, 8H, C6H5 ortho, JH-H=7.4, 1.6 Hz), 7.70 (m, 4H,
C6H5 ortho), 7.13-7.04 (m, 18H, C6H5 meta and para), 0.85 (d,
ortho), 7.44 (m, 8H, C6H5 ortho), 7.03 (m, 18H, C6H5 meta and
para), 5.68 (s, 2H, GeH). 13C{1H} NMR (75 MHz, THF-d8, rt):
δ 137.9 (C6H5 ipso), 136.6 (C6H5 ipso), 136.6 (C6H5 ortho), 136.3
(C6H5 ortho), 129.5 (C6H5 meta or para), 129.4 (C6H5 para),
129.1 (C6H5 meta or para), 129.0 (C6H5 meta). IR (KBr): 2012
(νGe-H) cm-1
.
Reaction of 3 with PhGeH3. To a stirred suspension of
complex 3 (81.4 mg, 0.065 mmol) in 3 mL of toluene was added
a 6-fold amount of PhGeH3 (59.6 mg, 0.39 mmol). The reaction
mixture was allowed to stir for 36 h at 60 °C, then filtered to
remove unreacted compounds and evaporated to give a pale
yellow solid. The resulting material was washed twice with
20 mL of hexane, dissolved in 5 mL of ether, then passed
through a Florisil column. The solvent was removed from the
eluted solutions in vacuo to give the tetragermane H(GePh2)4H14
as a white solid (39 mg, 66%). 1H NMR (300 MHz, C6D6, rt): δ
7.50 (d, 8H, C6H5 ortho, JH-H = 6.3 Hz), 7.38 (d, 8H, C6H5
ortho, JH-H = 6.0 Hz), 6.99 (m, 24H, C6H5 meta and para), 5.62
(s, 2H, GeH). 13C{1H} NMR (75 MHz, THF-d8, rt): δ 138.1
(C6H5 ipso), 137.0 (C6H5 ipso), 136.9 (C6H5 ortho), 136.4 (C6H5
ortho), 129.3 (C6H5 para), 129.2 (C6H5 para), 128.9 (C6H5 meta),
2
12H, PCH3, JP-H = 9.3 Hz, JPt-H = 25.5 Hz), 0.62 (m, 4H,
PCH2, 2JP-H = 16.7 Hz). 13C{1H} NMR (75 MHz, THF-d8, rt):
3
2
δ 147.5 (t, C6H5 ipso, JP-C =5.2 Hz, JPt-C =40 Hz), 147.2
(t, C6H5 ipso, 3JP-C=5 Hz, 2JPt-C=63 Hz), 137.8 (C6H5 ortho,
2JPt-C=18 Hz), 136.5 (C6H5 ortho), 127.9, 127.6, 127.3, 127.1
(C6H5 meta and/or para), 30.6 (m, PCH2), 14.7 (m, PCH3,
2
3JP-C = 28 Hz, JPt-C = 44 Hz). 31P{1H} NMR (121 MHz,
C6D6, rt): δ 36.2 (JPt-P=1819 Hz).
Preparation of [Pt(GePh2GePh2GePh2GePh2)(dmpe)] (3). A
mixture of 2 (101 mg, 0.098 mmol) and excess H2GePh2 (112 mg,
0.49 mmol) in toluene solution (3 mL) was heated for 48 h at
90 °C. The solvent was evaporated to dryness, and the resulting
white solid was recrystallized from toluene/hexane (1:4) to yield
3 as colorless crystals (35 mg, 29%). The 1H NMR spectrum of
the reaction mixture in C6D6 before purification showed two
Ge-H hydrogen signals at δ 5.57 and 5.68, which were assigned
to H(GePh2)2H13 and H(GePh2)3H14 (literature: δ 5.58 and
5.65). Anal. Calcd for C54H56Ge4P2Pt: C, 51.78; H, 4.51. Found:
C, 50.96; H, 4.57. 1H NMR (300 MHz, C6D6, rt): δ 7.72 (dd, 8H,
C6H5 ortho, JH-H = 6.6, 2.7 Hz), 7.50 (dd, 8H, C6H5 ortho,
128.9 (C6H5 meta). IR (KBr): 1998 (νGe-H) cm-1
.
X-ray Crystallography. Crystals of 1, 2, and 3 suitable for
an X-ray diffraction study were mounted on Micro-
Mounts (MiTeGen). The crystallographic data of 1 and 3 were
collected on a Rigaku Saturn CCD area detector equipped with
˚
monochromated Mo KR radiation (λ = 0.71073 A) at 150 K.
The data of 2 were collected on a Rigaku AFC-7R automated
four-cycle diffractometer at rt. Calculations were carried
out using the program package Crystal Structure, version 3.8,
for Windows. The positional and thermal parameters of non-
hydrogen atoms were refined anisotropically on F2 by the full-
matrix least-squares method using SHELXL-97.26 Hydrogen
atoms, except for the GeH hydrogens of 1, were placed at
calculated positions and refined with a riding mode on their
corresponding carbon atoms. Crystallographic data and details
of refinement of 1, 2, and 3 are summarized in Table 1.
J
H-H=7.7, 1.7 Hz), 7.07-6.92 (m, 24H, C6H5 meta and para),
2
0.79 (m, 12H, PCH3, JP-H =9.6 Hz, JPt-H =21.7 Hz), 0.61
(m, 4H, CH2, 2JP-H=17 Hz). 13C{1H} NMR (75 MHz, THF-d8,
rt): δ 148.4 (t, C6H5 ipso, 3JP-C = 5.5 Hz, 2JPt-C = 39 Hz), 141.9
(t, C6H5 ipso, 3JPt-C=14.4 Hz), 138.5 (C6H5 ortho, 2JPt-C=17.3
Hz), 137.6 (C6H5 ortho), 127.7 (C6H5 meta), 127.5 (C6H5 meta),
127.2 (C6H5 para), 127.1 (C6H5 para), 30.8 (m, PCH2), 13.9 (d,
2
2
PCH3, JP-C = 29 Hz, JPt-C = 39 Hz). 31P{1H} NMR (121
MHz, C6D6, rt): δ 33.6 (JPt-P=1851 Hz).
Direct Preparation of 3 from 1. Direct preparation of 3 from
complex 1 is as follows: Complex 1 (88 mg, 0.11 mmol),
H2GePh2 (251 mg, 1.10 mmol), and toluene (3 mL) were added
to a 25 mL Schlenk and stirred for 28 h at 90 °C. The solvent was
removed under reduced pressure to produce the residual solid,
which was recrystallized from toluene/hexane (1:4) to remove
oligogermanes as byproduct. The product 3 was obtained as
colorless crystals (84 mg, 61%).
Acknowledgment. This work was financially supported
by Grants-in-Aid for Scientific Research for Young
Chemists (No. 21750057), for Scientific Research (No.
1925008), and for Scientific Research on Priority Areas
(No. 19027018), from the Ministry of Education, Culture,
Sport, Science, and Technology, Japan. We are grateful
to Dr. Norio Nakata (Saitama University) for helpful
discussions.
Reaction of 2 with PhGeH3. When a 4-fold amount of PhGeH3
(108 mg, 0.71 mmol) was added to a 5 mL toluene solution of 2
(182 mg, 0.18 mmol), the reaction mixture turned from yellow
to colorless and was stirred for 2 h at rt. The reaction mixture
was filtered, and the solvent removed under reduced pressure.
The resulting solid material was reprecipitated with hexane
repeatedly to give H(GePh2)3H14 as a white solid (92.4 mg,
Supporting Information Available: Crystallographic data for
1, 2, and 3 as a CIF file. This material is available free of charge
(26) Sheldrick, G. M. SHELXL-97: Program for Crystal Structure
Refinement; University of Gottingen: Germany, 1997.
1
76%). H NMR (300 MHz, C6D6, rt): δ 7.60 (m, 4H, C6H5