Hideki Yorimitsu, Hiroshi Matsubara et al.
added to the solution by cannula. The mixture was stirred at room tem-
perature. After 20 min, the reaction was quenched with a saturated solu-
tion of NH4Cl and extracted with EtOAc. The organic layer was washed
with brine, dried (anhydrous Na2SO4), filtered, and concentrated in vacuo
to afford a white solid. The solid was suspended in hexane (5 mL), and
the suspension was then filtered off. The solid was washed on the filter
paper with hexane to afford 1b (1.02 g, 2.75 mmol, 23%). Colorless
solid; m.p. 170–1718C; 1H NMR (CDCl3): d=7.71–7.66 (m, 4H), 7.32–
7.27 (m, 6H), 3.77 (t, J=5.5 Hz, 6H), 2.76 (t, J=5.5 Hz, 6H), 0.57 ppm
(s, 3H); 13C NMR (CDCl3): d=140.91, 135.47, 127.83, 127.35, 57.95,
51.33, À2.87 ppm; 29Si NMR (CDCl3, 608C): d=À26.56, À69.02 ppm; IR
(neat): n˜ =1427, 1271, 1108, 1067, 910, 748, 735, 700, 629 cmÀ1; MS
(APCI-TOF): m/z: calcd for C19H25NO3Si2: 371.1367 [M]+; found:
371.1360; crystal data: C19H25NO3Si2, from 1,2-dichloroethane/EtOH,
M=371.58; orthorhombic, Pbca (No. 61), a=11.4397(3), b=24.7612(6),
640, 613 cmÀ1; MS (APCI-TOF): m/z: calcd for C9H21NO3Si2: 247.1054
[M]À; found: 247.1061.
1,1,2,2-Tetramethyl-1-phenyl-2-isopropoxydisilane
Ether (100 mL) and 1,2-dichloro-1,1,2,2-tetramethyldisilane (30 mmol,
5.56 mL) were added to a reaction flask purged with nitrogen. The mix-
ture was cooled to 08C. PhMgBr (0.47m in Et2O, 60 mL, 28.2 mmol) was
added. After stirring at 08C for 8 h, the resulting suspension was filtered
off and washed on the filter with hexane to collect the filtrate. After
evaporation, 1-chloro-2-phenyl-1,1,2,2-tetramethyldisilane was distilled
under reduced pressure (0.4 kPa, 898C, 4.29 g, 18.7 mmol, 62%). 4-Dime-
thylaminopyridine (2.5 mmol, 305.4 mg), imidazole (6.0 mmol, 408.5 mg),
and 1-chloro-2-phenyl-1,1,2,2-tetramethyldisilane (5.0 mmol, 1.14 mL)
were placed in a flask. The flask was purged with nitrogen, and DMF
(25 mL) was added. The mixture was cooled to 08C, and iPrOH
(10 mmol, 0.77 mmol) was added dropwise. The mixture was stirred at
room temperature for 3 h and then quenched by the addition of water.
The mixture was diluted with ether. The layers were separated, and the
aqueous layer was extracted with ether. The organic extracts were
washed with brine (3ꢂ), dried (anhydrous Na2SO4), filtered, and concen-
trated in vacuo to afford a colorless liquid. The product was distilled
under reduced pressure (0.3 kPa, 73–748C, 757 mg, 3.0 mmol, 60%). Col-
orless liquid; 1H NMR (CDCl3): d=7.53–7.48 (m, 2H), 7.37–7.30 (m,
3H), 3.87 (sept., J=5.9 Hz, 1H), 1.09 (d, J=5.9 Hz, 6H), 0.39 (s, 6H),
0.23 ppm (s, 6H); 13C NMR (CDCl3): d=139.40, 134.04, 128.59, 127.92,
66.05, 25.96, 0.26, À3.34 ppm; 29Si NMR (CDCl3, 608C): d=10.65,
À25.08 ppm; IR (neat): n˜ =1244, 1120, 1106, 1018, 876, 825, 786, 763, 731,
679, 633 cmÀ1; MS (APCI-TOF): m/z: calcd for C13H24OSi2: 251.1282
[M]À; found: 251.1270.
c=13.1386(3) ꢁ; V=3721.65(16) ꢁ3; Z=8; T=93 K; 1calcd =1.326 gcmÀ3
R1 =0.0516 [I>2.0 s(I)]; wR2 =0.1183 (all data); GOF=1.077.
;
DimethylACHTUNGTRENNUNG(o-tolyl)silylsilatrane (1c)
Et2O (15 mL) and dichlorodimethylsilane (60 mmol, 9.0 mL) were added
to a reaction flask purged with nitrogen. The mixture was cooled to 08C.
2-Methylphenylmagnesium bromide (0.62m in THF, 81 mL, 50 mmol)
was added at 08C by cannula to the solution, which was warmed to room
temperature. The mixture was stirred overnight, and the resulting suspen-
sion was filtered off and washed on the filter with hexane to collect the
filtrate. After evaporation of the solvent, chlorodimethylACTHNUTRGNE(UNG o-tolyl)silane
was distilled under reduced pressure (0.4 kPa, 788C, 5.37 g, 29.0 mmol,
58%). Lithium wire (500 mg, 70 mmol) in oil was cut into 4 mm cubes
with scissors. These lithium cubes were stirred vigorously for 10 min in
hexane (5 mL) under an atmosphere of nitrogen. The hexane was re-
moved and the lithium was suspended in THF (15 mL). The mixture was
Representative procedure for the silylation of electron-rich and electron-
neutral aryl chlorides
stirred rapidly with chlorodimethyl
ACHTUNGTRENNUNG
room temperature for 6 h to give a deep red solution of Me CTHUNGTRENNUNG
Pd2ACTHNUTRGNEUNG(dba)3 (0.015 mmol, 13.7 mg) and SPhos (0.045 mmol, 18.5 mg) were
(ꢀ1.0m). Ethoxysilatrane (2.44 g, 12 mmol) was placed in a reaction
added to a flask. The flask was purged with argon, and toluene (0.5 mL)
was added. The mixture was then stirred at room temperature for 10 min.
4-Chloroanisole (0.50 mmol, 71.2 mg) was added, and then the mixture
was stirred at room temperature for 5 min. Dimethylphenylsilylsilatrane
(1a; 0.60 mmol, 185.7 mg) and toluene (1.0 mL) were added. The mixture
was then stirred at 1008C for 12 h. The resulting mixture was diluted
with EtOAc and passed through a short column of alumina by washing
copiously with EtOAc. Chromatographic purification (silica gel, EtOAc/
hexane=1:40) afforded 2a (108 mg, 0.444 mmol, 89%).
flask. The reaction flask was purged with nitrogen, and THF (20 mL) was
added to the reaction flask. Dimethyl
N
THF, 18 mL, 18 mmol) was added to the solution by cannula. The mix-
ture was stirred at room temperature. After 30 min, the reaction was
quenched with a saturated solution of NH4Cl and extracted with EtOAc.
The organic layer was washed with brine, dried (anhydrous Na2SO4), fil-
tered, and concentrated in vacuo to afford a white solid. The solid was
suspended in hexane (5 mL), and the suspension was then filtered off.
The solid was washed on the filter paper with hexane to afford 1c
(486 mg, 1.50 mmol, 13%). Colorless solid; m.p. 143–1448C; 1H NMR
(CDCl3): d=7.56 (d, J=6.4 Hz, 1H), 7.17 (t, J=7.8 Hz, 1H), 7.13–7.07
(m, 2H), 3.72 (t, J=5.5 Hz, 6H), 2.76 (t, J=5.5 Hz, 6H), 2.52 (s, 3H),
0.35 ppm (s, 6H); 13C NMR (CDCl3): d=144.52, 140.72, 135.21, 129.29,
128.11, 124.58, 58.32, 51.57, 23.35, À1.06 ppm; 29Si NMR (CDCl3, 608C):
d=À25.62, À65.51 ppm; IR (neat): n˜ =1453, 1274, 1110, 1075, 874, 812,
Representative procedure for the silylation of electron-deficient and
electron-neutral aryl chlorides
Under an inert atmosphere, Pd
ACHTUNGTRNE(NUNG PtBu3)2 (0.025 mmol, 12.8 mg) was added
to flask. Toluene (1.0 mL) and 1-chloro-4-trifluoromethyltoluene
a
740, 624, 588 cmÀ1
; MS (APCI-TOF): m/z: calcd for C15H25NO3Si2:
(0.50 mmol, 90.9 mg) were added, and then the mixture was stirred at
room temperature for 5 min. Dimethylphenylsilylsilatrane (1a;
0.60 mmol, 185.7 mg) was added, and the mixture was then stirred at
1008C for 10 h. The resulting mixture was diluted with EtOAc and
passed through a short column of alumina by washing copiously with
EtOAc. Chromatographic purification (silica gel, hexane) afforded 2g
(140 mg, 0.499 mmol, 99%).
Products 2a,[32] 2d,[33] 2 f,[34] 2g,[32] 2h,[32] 2l,[32] 3,[33] 4,[35] and 5[36] are
known compounds and showed spectral data that were identical to those
given in the literature.
323.1367 [M]+; found: 323.1352.
Trimethylsilylsilatrane (1d)
Ethoxysilatrane (6.58 g, 30 mmol) and THF (40 mL) were added to a re-
action flask under an atmosphere of nitrogen. Trimethylsilyllithium[31]
(ꢀ0.24m in THF, 62 mL, 15 mmol) was added to the solution by cannula.
The mixture was stirred overnight at room temperature. The reaction
was quenched with a saturated solution of NH4Cl and extracted with
EtOAc. The organic layer was washed with brine, dried (anhydrous
Na2SO4), filtered, and concentrated to afford a white solid. The solid was
suspended in hexane (5 mL) and then filtered off. The solid was washed
on the filter paper with hexane to afford 1d (1.04 g, 4.2 mmol, 28%).
Colorless solid; m.p. 171–1748C; 1H NMR (CDCl3): d=3.73 (t, J=
5.5 Hz, 6H), 2.76 (t, J=5.5 Hz, 6H), 0.04 ppm (s, 9H); 13C NMR
(CDCl3): d=58.29, 51.47, À0.81 ppm; 29Si NMR (CDCl3, 608C): d=
À23.85, À64.03 ppm; IR (neat): n˜ =1110, 1077, 935, 849, 824, 744, 726,
(4-tert-Butyldimethylsiloxyphenyl)dimethylphenylsilane (2b)
Colorless oil; 1H NMR (CDCl3): d=7.53–7.48 (m, 2H), 7.39–7.31 (m,
5H), 6.83 (d, J=8.3 Hz, 2H), 0.98 (s, 9H), 0.52 (s, 6H), 0.20 ppm (s,
6H); 13C NMR (CDCl3): d=156.84, 138.92, 135.76, 134.30, 129.74, 129.11,
127.90, 119.79, 25.83, 18.34, À2.01, À4.20 ppm; 29Si NMR (CDCl3, RT):
d=20.62, À8.45 ppm; IR (neat): n˜ =1591, 1500, 1428, 1253, 1175, 1109,
&
&
4
Chem. Asian J. 2014, 00, 0 – 0
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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