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M.L. Amadoruge et al. / Journal of Organometallic Chemistry 693 (2008) 1771–1778
CH3CN (44 lL, 0.84 mmol) and LiNPri2 (0.090 g,
0.84 mmol) and 1c was isolated as a colorless oil.
4.10. Preparation of Pri3GeGePh3 (3) using 4a
1
Yield = 0.147 g, 64%. H NMR (C6D6, 25 °C) d 1.59 (s,
To a solution of 4a (0.778 g, 3.16 mmol) in acetonitrile
(20 mL) in a Schlenk tube was added a solution of
Ph3GeH (1.239 g, 4.062 mmol) in acetonitrile (10 mL).
The tube was sealed and the reaction mixture was heated
at 85 °C for 48 h. The volatiles were removed in vacuo
and the crude product was distilled in a Kugelrohr oven
(180 °C, 0.05 torr) to remove excess Ph3GeH which fur-
nished 3 (1.451 g, 91%) as a colorless solid. 1H NMR
(C6D6, 25 °C) d 7.72–7.68 (m, 6H, meta-H), 7.20–7.15
(m, 9H, para- and ortho-H), 1.67 (sept, J = 7.5 Hz, 3H,
CH3CHCH3), 1.18 (d, J = 7.5 Hz, 18H, CH3CHCH3)
ppm. 13C NMR (C6D6, 25 °C) d 139.8 (ipso-C), 135.9
(ortho-C), 128.6 (meta-C), 128.5 (para-C), 21.3
(CH3CHCH3), 16.8 (CH3CHCH3) ppm. UV–Vis: kmax
234 nm (br, e 3.82 ꢁ 104 cmꢀ1 Mꢀ1). Anal. Calc. for
C27H36Ge2: C, 64.12; H, 7.17. Found: C, 63.88; H,
6.97%.
2H, –CH2CN), 1.06 (s, 27H, –C(CH3)3) ppm. 13C NMR
(C6D6, 25 °C) d 123.2 (–CH2CN), 31.4 (–C(CH3)3), 30.2
(–C(CH3)3), 28.3 (–CH2CN) ppm.
4.6. Preparation of Ph3GeGePh3(2) using 1a
The same procedure used for the synthesis of 3 (Sec-
tion 4.10, vide infra) from 4a was employed starting with
1a (0.315 g, 0.916 mmol) and Ph3GeH (0.282 g,
0.925 mmol) yielding Ph3GeGePh3 (2) (0.488 g, 88%).
Anal. Calc. for C36H30Ge2: C, 71.14; H, 4.97. Found:
C, 71.02; 5.04%.
4.7. Preparation of Ph3GeGePri3 (3) using 1b
The same procedure used to prepare 3 from 4a (Section
4.10, vide infra) was employed starting with 1b (0.255 g,
1.05 mmol) and Ph3GeH (0.332 g, 1.09 mmol) yielding 3
(0.461 g, 87%).
4.11. Preparation of But3Ge[NHC(CH3)CHCN] (8)
To a solution of 4b (0.281 g, 0.976 mmol) in CH3CN
(5 mL) was added a solution of Ph3GeH (0.299 g, 0.981
g) in CH3CN (10 mL). The reaction mixture was sealed
in a Schlenk tube and was heated at 85 °C for 72 h. The sol-
vent was removed in vacuo to yield a yellow oil. The crude
material was distilled in a Kugelrohr oven (120 °C,
0.050 torr) resulting in the collection of a clear oil which
was isolated (0.147 g) and identified to be pure But3GeN-
Me2. A new receiving flask was attached to the apparatus
and distillation was continued (180 °C, 0.05 torr) resulting
in the isolation of a yellow oil (0.338 g) which consisted of a
mixture of 8, 4b, and Ph3GeH as shown by 1H NMR spec-
troscopy. Recrystallization of the product from hexane
(ꢂ3 mL) at ꢀ35 °C afforded 8 as colorless crystals
(0.020 g, 6.3%). 1H NMR (C6D6, 25 °C) d 4.33 (s, 1H,
C@CHCN), 3.18 (br s, 1H, Ge–NH), 1.94 (s, 3H, H3C–
4.8. Preparation of Pri3GeNMe2 (4a)
To a solution of Pri3GeCl (1.00 g, 4.21 mmol) in benzene
(15 mL) was added a suspension of LiNMe2 (0.225 g,
4.42 mmol) in benzene (20 mL). The resulting suspension
was stirred for 24 h and then filtered through Celite. The
volatiles were removed from the filtrate in vacuo to yield
4a (0.778 g, 75%) as a colorless oil. 1H NMR (C6D6,
25 °C) d 2.67 (s, 6H, –N(CH3)2), 1.42 (sept, J = 7.2 Hz,
3H, CH3CHCH3), 1.10 (d, J = 7.2 Hz, 18H, CH3CHCH3)
ppm. 13C NMR (C6D6, 25 °C) d 42.2 (–N(CH3)2), 18.8
(CH3CHCH3), 15.7 (CH3CHCH3) ppm. Anal. Calc. for
C11H27GeN: C, 53.72; H, 11.07. Found: C, 53.81; H,
11.11%.
4.9. Synthesis of But3GeNMe2 (4b)
C@C), 1.08 (s, 28H, –C(CH3)3) ppm. H NMR (CD3CN,
1
25 °C) d 4.09 (s, 1H, C@CHCN), 3.84 (br s, 1H, Ge–
NH), 2.14 (s, 3H, H3C–C@C), 1.25 (s, 28H, –C(CH3)3)
ppm. 13C NMR (CD3CN, 25 °C) d 135.8 (–CN), 130.2
(N–C@C), 129.4 (N–C@C), 66.0 (C@C–CH3), 31.5 (–
C(CH3)3) 30.7 (–C(CH3)3) ppm. Anal. Calc. for
C16H32GeN2: C, 59.13; H, 9.92. Found: C, 58.92; H,
9.97%.
To a solution of But3GeCl (0.500 g, 1.79 mmol) in THF
(20 mL) was added a solution of LiNMe2 (0.091 g,
1.79 mmol) in THF (10 mL). The reaction mixture was
refluxed for 18 h and the solvent was removed in vacuo.
The resulting solid was dissolved in benzene, filtered
through Celite, and the volatiles were removed in vacuo
to yield a pale yellow semisolid. The crude product was dis-
tilled in a Kugelrohr oven (125 °C, 0.07 torr) to yield 4b
4.12. NMR tube reaction of But3GeNMe2 with Ph3GeH
1
(0.315 g, 61%) as a colorless oil. H NMR (C6D6, 25 °C)
d 2.71 (s, 6H, –N(CH3)2), 1.19 (s, 27H, –C(CH3)3) ppm.
1H NMR (CD3CN, 25 °C) d 2.63 (s, 6H, –N(CH3)2), 1.27
(s, 27H, –C(CH3)3) ppm. 13C NMR (C6D6, 25 °C) d
41.9 (–N(CH3)2), 32.8 (–C(CH3)3), 29.9 (–C(CH3)3) ppm.
13C NMR (CD3CN, 25 °C) d 42.2 (–N(CH3)2), 31.6
(–C(CH3)3), 30.2 (–C(CH3)3) ppm. Anal. Calc. for
C14H33GeN: C, 58.38; H, 11.55. Found: C, 58.03; H,
11.67%.
A solution of 4b (0.025 g, 0.087 mmol) in CD3CN
(0.5 mL) was prepared in a Kontes screw-cap NMR tube.
The sample was heated at 85 °C for 6 days during which
time the 13C NMR spectrum was recorded at regular inter-
vals. After this time, Ph3GeH (0.027, 0.088 mmol) was
added to the tube and the sample was heated at 85 °C for
24 h. The 13C NMR spectrum was recorded and the sample
was heated at 85 °C for a further 72 h.