1854 Organometallics, Vol. 15, No. 7, 1996
Driess et al.
7.36 (m, 5 H, arom H); 31P NMR (C6D6, 300 K) δ -25.4 (s);
29Si NMR (C6D6, 300 K) δ 15.1 (dd, SiH, 1J (Si,H) ) 198 Hz,
1J (Si,P) ) 5.1 Hz), -0.9 (d, Is2Si, 1J (Si,P) ) 47 Hz); EI-MS
(m/ z (%)) 711 (6) [M+], 591 (5) [(M - C3H7 - Ph)+], 435 (100)
[Is2SiH+], 77 (100) [Ph+]; HRMS calcd for C45H70NPSi2 m/ z
711.4765, found m/ z 711.4764.
27.06 (s), 30.32 (s), 33.20 (s), 34.50 (s), 35.03 (s), 36.09 (s), 88.21
(d, PCO, J (C,P) ) 23.3 Hz), 121.54 (s), 122.85 (s), 123.89 (s),
1
125.96 (s), 149.78 (s), 150.77 (s), 154.30 (s), 156.10 (s). EI-MS
(m/ z (%)) 805 (8) [M+], 648 (24) [(M - SiiPr3)+], 623 (100) [(M
- OCPh2)+], 433 (96) [(Is2Si - 1H)+]. Anal. Calcd for
C
52H77OPSi2: C, 77.55; H, 9.63; P, 3.84. Found: C, 77.21; H,
9.62; P, 3.90.
Syn th esis of Is2SiAs(SiCy2Me)C(P h )dN (20). A solution
of 208 mg (0.29 mmol) of 4c in 10 mL of toluene was treated
with 29.9 mg (0.29 mmol) of benzonitrile at -60 °C. The
mixture was allowed to warm to room temperature within 3
h to afford a pale yellow solution. Removal of the solvent in
vacuum (10-2 Torr) and recrystallization from 2 mL of hexane
afforded a colorless solid: Yield 167 mg (0.20 mmol, 69%); fp
254-256 °C; 1H NMR (C6D6, 300 K) δ 0.61 (br, 3 H, SiMe),
0.98-1.60 (m, 58 H, C6H11 and CHMe2), 2.57 (br, 2 H,
p-CHMe2), 3.67 (br, 2 H, o-CHMe2), 4.07 (br, 2 H, o-CHMe2),
6.92, 7.46-7.43 (br, 9 H, arom H); 29Si NMR (C6D6, 300 K) δ
14.2 (s, SiMeCy2), -12.7 (s, Is2Si); EI-MS (m/ z (%)) 821 (3)
[M+], 718 (10) [(M - PhCN)+], 435 (100) [Is2SiH+]; HRMS calcd
for C44H67AsNSi2 m/ z 821.4712, found m/ z 821.4709.
Th er m olysis of 23 in to Is2SiOSiIs2O (24), P h 2CdP -
(SiiP r 3) (25), a n d P h (SiiP r 3)CdP (P h ) (25A). Heating of a
solution of 23 (300 mg, 0.37 mmol) in toluene at 160 °C for 2
d in a sealed NMR tube afforded a mixture of the three
products 24, 25, and 25A which were identified by NMR
spectroscopy and mass spectrometry. The recorded 29Si NMR
spectroscopic data of 24 are identical with those reported in
the literature.34 Selected 13C{1H} NMR data of 25: δ 201.0
1
(d, CdP, J (C,P) ) 88 Hz). 31P NMR (C6D6): δ 293.7 (s). 29Si
1
NMR: δ 28.4 (d, SiiPr3, J (Si,P) ) 63 Hz). EI-MS (m/ z (%))
354 (34) [M+], 197 (82) [(M - SiiPr3)+], 43 (100) [C3H7+].
1
Selected 13C{1H} NMR data of 25A: δ 189.0 (d, CdP, J (C,P)
) 67 Hz). 31P NMR (C6D6): δ 281.9 (s). 29Si NMR: δ 12.2 (d,
SiiPr3, 2J (Si,P) ) 17 Hz). EI-MS (m/ z (%)) 354 (34) [M+], 280
(41) [(M - Ph)+], 43 (100) [C3H7+]. HRMS: calcd for C22H31
PSi, m/ z 354.1924, found, m/ z 354.1918.
-
Syn th esis of Is2SiAs(SiCy2Me)P dC(tBu ) (21). A solu-
tion of 250 mg (0.34 mmol) of 4a in 0.2 mL of tert-butylphos-
phaacetylene was heated in a sealed NMR tube at 120 °C for
2 d. The reaction process was monitored by 31P and 29Si NMR
spectroscopy. Removal of volatile components in vacuum (10-2
Torr) and recrystallization of the residue from 1 mL of hexane
at -80 °C afforded a yellow solid: Yield 105 mg (0.13 mmol,
Rea ction of 2a w ith P h C(O)C(O)P h a n d 1,2,3,5-C6H2-
(CO)2(tBu )2 To F or m Is2SiP (SiiP r 3)OC(P h )dC(P h )O (26),
Is2SiP (SiiP r 3)C(P h )(COP h )O (27), a n d Is2SiP (SiiP r 3)-1-
O-3,5-C6H2(tBu )2-2-O (28). 26, 27: A solution of 300 mg (0.48
mmol) of 2a in 20 mL of toluene was reacted with 100.8 mg
(0.48 mmol) of PhC(O)C(O)Ph at -80 °C. The resulted
colorless solution was slowly warmed to room temperature.
At this stage, a mixture of 26 and 27 (1:9) was formed, from
which the compound 26 could not be isolated. Therefore, 26
was characterized only by 31P NMR spectroscopy (δ 116.3 (s)).
Upon heating of this mixture at 110 °C for 3 h, the intermedi-
ate 26 was completely transformed into 27. The latter was
isolated by crystallization from 1 mL of hexane: Yield 312 mg
(0.38 mmol, 78%) of a colorless solid: fp 177 °C; 1H NMR (C6D6,
300 K) δ 0.39 (d, 3 H, CHMe2, J (H,H) ) 6.1 Hz), 0.56 (d, 3 H,
CHMe2, J (H,H) ) 6.4 Hz), 0.72 (d, 3 H, CHMe2, J (H,H) ) 6.4
Hz), 0.97 (d, 3 H, CHMe2, J (H,H) ) 6.8 Hz), 1.03-1.32 (m, 39
H, CHMe2), 1.52 (d, 3 H, CHMe2, J (H,H) ) 6.5 Hz), 1.78 (sept,
3 H, SiCHMe2, J (H,H) ) 7.5 Hz), 2.60 (sept, 1 H, p-CHMe2,
J (H,H) ) 6.9 Hz), 2.74 (sept, 1 H, p-CHMe2, J (H,H) ) 6.9 Hz),
2.94 (sept, 1 H, o-CHMe2, J (H,H) ) 6.1 Hz), 3.41 (sept, 1H,
o-CHMe2, J (H,H) ) 6.4 Hz), 4.02 (sept, 1 H, o-CHMe2, J (H,H)
) 6.5 Hz), 4.52 (sept, 1 H, o-CHMe2, J (H,H) ) 6.5 Hz), 6.65-
8.16 (m, 14 H, arom H); 31P NMR (C6D6, 300 K) δ -32.9 (s);
1
38%); fp 254-256 °C; H NMR (C6D6, 300 K) δ 0.71 (br, 3 H,
SiMe), 0.98-1.65 (m, 67 H, C6H11, tBu and CHMe2), 2.78 (br,
2 H, p-CHMe2), 3.99 (br, 2 H, o-CHMe2), 4.23 (br, 2 H,
o-CHMe2), 6.92 (br, 4 H, arom H); 29Si NMR (C6D6, 300 K) δ
2
16.9 (s, SiMeCy2), 11.8 (d, Is2Si, J (Si,P) ) 8 Hz); 31P NMR δ
1
387 (s); selected 13C{1H} NMR data δ 240.5 (d, CdP, J (C,P)
) 82.7 Hz); EI-MS (m/ z (%)) 818 (1) [M+], 718 (5) [(M -
tBuCP)+], 435 (100) [Is2SiH+]; HRMS calcd for C48H80AsPSi2
m/ z 818.4731, found m/ z 818.4725.
[2 + 4]-Cycloa d d ition Rea ction of 2a w ith Cyclop en -
ta d ien e To F or m 22. A 200 mg (0.32 mmol) amount of 2a
in 5 mL of toluene was mixed with 21.1 mg of cyclopentadiene
and stirred at room temperature for 5 h. Removal of the
solvent afforded 221 mg (0.32 mmol, 100%) of the pure product
1
in form of a colorless solid: fp 153-155 °C; H NMR (C6D6,
300 K) δ 0.38 (d, 3 H, CHMe2, J (H,H) ) 7 Hz), 0.67 (d, 3 H,
CHMe2, J (H,H) ) 7 Hz), 1.17-1.67 (m, 51 H, CHMe2), 2.34
(d, 1 H, AM-spin system, CH2-bridge, J (H,H) ) 11.5 Hz), 2.40
(br, 1 H, CHMe2), 2.62 (m, 2 H, p-CHMe2), 3.31 (br, 1 H,
CHMe2), 3.41 (d, 1 H, CH2-bridge, J (H,H) ) 11.5 Hz), 3.75 (m,
2 H, CHCdC), 5.31 (m, 1 H, HCdCH), 5.44 (m, 2 H, CHMe2),
6.11 (m, 1 H, HCdCH), 6.30 (d, 1 H, arom H, J (H,H) ) 12.8
Hz), 7.00 (br, 2 H, arom H), 7.13 (d, 1 H, arom H, J (H,H) )
12.8 Hz); 31P NMR (C6D6, 300 K) δ -153.4 (s); 29Si NMR (C6D6)
1
29Si NMR (C6D6) δ 9.9 (d, SiiPr3, J (Si,P) ) 7 Hz), 1.3 (d, IsSi,
1J (Si,P) ) 4 Hz); selected 13C{1H} NMR (C6D6) data δ 92.95
(d, P-C, 1J (C,P) ) 23.3 Hz), 198.21 (s, CdO); IR (ν(CO)) 1642
cm-1; EI-MS (m/ z (%)) 833 (36) [M+], 645 (38) [(M - SiiPr3)+],
434 (58) [(Is2SiH)+], 105 (100) [PhCO+]. Calcd for C53H77O2-
PSi2: C, 76.38; H, 9.31; P, 3.71; Found: C, 76.10; H, 9.29; P,
3.80.
1
1
δ 15.1 (d, SiiPr3, J (Si,P) ) 71.4 Hz), -4.8 (d, IsSi, J (Si,P) )
31.8 Hz); EI-MS (m/ z (%)) 688 (8) [M+], 622 (42) [(M - C5H6)+],
434 (100) [(Is2SiH - 1)+]; HRMS calcd for C44H73PSi2 m/ z
688.4969, found m/ z 688.4960.
28. A solution of 312 mg (0.5 mmol) of 2a in 10 mL of
toluene was treated with 110 mg (0.5 mmol) of 3,5-di-tert-butyl-
o-benzoquinone at -78 °C. During the addition, the intense
color of the quinone disappeared immediately and a colorless
solution was formed after warming to room temperature.
Removal of the solvent in vacuum (10-2 Torr) and crystalliza-
tion of the residue from a little hexane at -78 °C afforded a
colorless solid: Yield 400 mg (0.47 mmol, 94%); fp 191-192
°C; 31P NMR (C6D6, 300 K) δ 114.3 (s); 29Si NMR (C6D6) δ 16.6
(d, SiiPr3, 1J (Si,P) ) 53.1 Hz), -8.6 (d, IsSi, 1J (Si,P) ) 69 Hz);
EI-MS (m/ z (%)) 842 (81) [M+], 685 (86) [(M - SiiPr3)+], 628
(30) [(M - SiiPr3 - C4H9)+], 57 (100) [C4H9+]. Calcd for
Syn th esis of Is2SiP (SiiP r 3)CP h 2O (23). A 340 mg (0.54
mmol) amount of 2a in 10 mL of toluene was reacted with 98.3
mg (0.54 mmol) of benzophenone at -78 °C. The reaction
mixture was warmed to room temperature, and the solvent
was removed (10-2 Torr), followed by crystallization of the
product from 1 mL of hexane at room temperature: Yield 382
mg (0.47 mmol, 88%); fp 148 °C; 1H NMR (C6D6, 300 K) δ 0.28
(br, 3 H, CHMe2), 0.47 (br, 3 H, CHMe2), 1.07-1.58 (m, 51 H,
CHMe2), 2.73 (sept, 2 H, p-CHMe2, J (H,H) ) 6.8 Hz), 3.00 (br,
1 H, o-CHMe2), 3.59 (br, 1 H, o-CHMe2), 4.70 (br, 1 H,
o-CHMe2), 4.84 (br, 1 H, o-CHMe2), 6.75-7.25 (m, 10 H, arom
H), 7.73 (s, 2 H, arom H), 7.77 (s, 2 H, arom H); 31P NMR (C6D6,
C
53H87O2PSi2: C, 75.47; H, 10.39; P, 3.67. Found: C, 76.00;
H, 10.41; P, 3.48.
1
300 K) δ -18.8 (s); 29Si NMR (C6D6) δ 16.8 (d, SiiPr3, J (Si,P)
) 75 Hz), 8.2 (d, IsSi, 1J (Si,P) ) 4.9 Hz); 13C{1H} (C6D6) δ 15.4
(34) Watanabe, H.; Takeuchi, K.; Nakajima, K.; Nagai, Y.; Goto, M.
Chem. Lett. 1988, 1343.
2
(d, SiCHMe2, J (C,P) ) 8.7 Hz), 20.38 (s), 24.72 (s), 25.65 (s),