M. Oestreich et al.
3
1
0
.10 mmol, 67% purity) was dissolved in 1,2-C
6
H
4
F
2
(0.3 mL), and ben-
(96 MHz, C
9.2 ppm.
6 6 6 6
D ): d=0.0 ppm (br s); P NMR (121 MHz, C D ): d=
zaldehyde (15 mg, 0.14 mmol) was added. The deep orange solution was
layered with n-hexane (1 mL). The title compound was obtained as
orange microcrystalline needles. Yield: 28 mg (0.50 mmol, 50%).
(
S)-4-(Pentafluorophenyl)-4,5-dihydro-3H-dinaphtho[2,1-c:1’,2’-e]bor-
epine pyridine adduct (3·py): A sample of 3·THF (13 mg, 0.024 mmol)
was dissolved in 1,2-C H F (0.5 mL), and pyridine (1.9 mg, 0.024 mmol)
was added. All solvents were removed under vacuum to obtain the title
compound as a crystalline solid in quantitative yield. H NMR (300 MHz,
C D ): d=2.05 (d, AB spin system, J=13.4 Hz, 1H, BCH ), 2.37 (d, AB
spin system, J=11.4 Hz, 1H, BCH ), 2.49 (d, AB spin system, J=
11.4 Hz, 1H, BCH ), 3.04 (d, AB spin system, J=13.2 Hz, 1H, BCH ),
1
H NMR (300 MHz, C
), 2.69 (d, AB spin system, J=13.8 Hz, 2H, BCH
.7 Hz, J=7.7 Hz, 2H, meta-PhCHO), 6.97 (m, 1H, para-PhCHO), 7.01
ddd, J=8.5 Hz, J=6.7 Hz, J=1.2 Hz, 2H), 7.16–7.24 (m, 4H, ortho-
PhCHO and Np), 7.28 (d, J=8.3 Hz, 2H), 7.58 (d, J=8.5 Hz, 2H), 7.66
d, J=8.2 Hz, 2H), 7.75 (d, J=8.1 Hz, 2H), 8.74 ppm (s, 1H, PhCHO);
6
D
6
): d=2.66 (d, AB spin system, J=13.7 Hz, 2H,
6
4 2
BCH
7
(
2
2
), 6.78 (dd, J=
1
6
6
2
2
(
2
2
1
3
C NMR (100 MHz, C
6
D
6
): d=33.3 (br s, BCH
2
), 124.9, 126.3, 127.5,
6.17–6.21 (m, 2H, pyridine), 6.57–6.61 (m, 2H, pyridine and Np), 7.05
(m, 2H), 7.20 (m, 2H), 7.37 (d, J=8.3 Hz, 1H), 7.52 (d, J=8.2 Hz, 1H),
7.68 (d, J=8.4 Hz, 1H), 7.70–7.80 ppm (m, 6H, pyridine and Np);
1
1
27.6, 128.1, 128.6, 128.8, 129.3, 131.8, 132.8, 133.3, 134.2, 136.9, 138.9,
1
9
94.2 ppm (signals for carbon atoms of C
6
F
5
not resolved); F NMR
), ꢀ154.9 (t, J=20.8 Hz, 1F,
); B NMR (96 MHz, C ): d=
1
3
(
282 MHz, C
6
D
6
): d=ꢀ131.1 (m, 2F, o-C
6
1
F
5
6 6 2 2
C NMR (100 MHz, C D ): d=31.5 (br s, BCH ), 34.5 (br s, BCH ),
1
p-C
6
F
5
), ꢀ163.0 ppm (m, 2F, m-C
6
F
5
6
D
6
124.2, 124.3, 124.9 (pyridine), 125.9, 126.1, 126.9, 127.2, 127.2, 127.6,
127.8, 127.9, 128.3, 128.8, 132.3, 132.6, 132.8, 133.0, 133.2, 133.9, 139.7
3
4.5 ppm (br s).
S)-4-(Pentafluorophenyl)-4,5-dihydro-3H-dinaphtho[2,1-c:1’,2’-e]bor-
epine acetonitrile adduct (3·MeCN): A sample of the crude 3 (45 mg,
.066 mmol, 67% purity) was dissolved in 1,2-C (0.3 mL), and
(
pyridine), 143.0, 143.1, 145.2 ppm (pyridine) (signals for carbon atoms of
(
1
9
C
6
F
F
5
not resolved); F NMR (282 MHz, C
), ꢀ157.8 (t, J=20.8 Hz, 1F, p-C ), ꢀ163.4 ppm (m, 2F, m-C
): d=5.3 ppm (br s).
S)-4-(Pentafluorophenyl)-4,5-dihydro-3H-dinaphtho[2,1-c:1’,2’-e]bor-
6
D
6
): d=ꢀ131.5 (m, 2F, o-
C
6
5
6
F
5
6 5
F
);
0
6 4 2
H F
1
1
6 6
B NMR (96 MHz, C D
MeCN (2 drops) was added. The yellow solution was layered with n-
hexane (1 mL) and cooled to ꢀ358C. The title compound was obtained
(
1
epine tert-butyl isocyanide adduct (3·tBuNC):
A
sample of 3·THF
as white pellets. Yield: 31 mg (0.063 mmol, 95%). H NMR (300 MHz,
(
60 mg, 0.11 mmol, 1.0 equiv) was dissolved in 1,2-C H F (1 mL), and
6 4 2
C
6
D
6
): d=0.23 (s, 3H, CH
3
CN), 2.41 (d, AB spin system, J=12.8 Hz,
), 7.01 (ddd,
tBuNC (9.4 mg, 0.11 mmol, 1.0 equiv) was added. All volatiles were re-
moved under vacuum to obtain the title compound as a crystalline solid
2
H, BCH ), 2.44 (d, AB spin system, J=12.8 Hz, 2H, BCH
2
2
J=8.3 Hz, J=6.8 Hz, J=1.3 Hz, 2H), 7.21 (ddd, J=8.1 Hz, J=6.8 Hz,
J=1.1 Hz, 2H), 7.43 (d, J=8.3 Hz, 2H), 7.63 (d, J=8.5 Hz, 2H), 7.78 (d,
1
in quantitative yield. H NMR (300 MHz, C
6
D
6
): d=0.57 (s, 9H, tBuNC),
), 2.23 (d, AB spin
), 2.35 (d, AB spin system, J=12.7 Hz,
), 2.80 (d, AB spin system, J=12.4 Hz, 1H, BCH ), 7.01 (m,
2H), 7.21 (m, 2H), 7.39 (d, J=8.2 Hz, 1H), 7.49 (d, J=8.4 Hz, 1H), 7.60
d, J=8.3 Hz, 1H), 7.62 (d, J=8.4 Hz, 1H), 7.74 (d, J=8.2 Hz, 1H), 7.79
1
3
2.09 (d, AB spin system, J=12.5 Hz, 1H, BCH
system, J=12.7 Hz, 1H, BCH
H, BCH
2
J=8.3 Hz, 2H), 7.82 ppm (d, J=8.1 Hz, 2H); C NMR (100 MHz,
CN), 32.0 (br s, BCH ), 113.4 (br s, CH CN), 124.4,
26.0, 127.4, 127.5, 128.3, 128.4, 132.6, 133.4, 133.5, 142.3 ppm (signals for
2
C
1
6
D
6
): d=ꢀ0.5 (CH
3
2
3
1
2
2
1
9
carbon atoms of C
6
F
5
not resolved); F NMR (282 MHz, C
), ꢀ158.0 (t, J=21.3 Hz, 1F, p-C ), ꢀ163.8 ppm
); B NMR (96 MHz, C ): d=3.0 ppm (br s).
S)-4-(Pentafluorophenyl)-4,5-dihydro-3H-dinaphtho[2,1-c:1’,2’-e]bor-
6 6
D ): d=
(
ꢀ
131.6 (m, 2F, o-C
6
F
5
6 5
F
1
3
1
1
(d, J=8.2 Hz, 2H), 7.84 ppm (d, J=8.1 Hz, 1H); C NMR (100 MHz,
): d=28.4 (tBuNC), 29.4 (br s, BCH ), 30.5 (br s, BCH ), 58.7
tBuNC), 119.2 (m, ipso-C ), 124.3, 124.4, 125.8, 126.1, 127.1, 127.1,
27.7, 127.8, 127.9, 128.2, 128.7, 128.8, 132.5, 132.7, 133.0, 133.1, 133.4,
33.6, 137.4 (dm, J=254 Hz, m-C ), 139.6 (dm, J=249 Hz, p-C ),
41.7, 142.9, 148.5 pm (dm, J=243 Hz, o-C ) (no signal for isonitrile
): d=ꢀ130.8 (m, 2F, o-
), ꢀ163.6 ppm (m, 2F, m-C );
): d=ꢀ13.9 ppm.
Determination of the Lewis acidity of 3 and B
Beckett method in CD Cl and C : The 3·R
pared by dissolving 3·THF (10–11 mg) and the indicated phosphine oxide
1.0 equiv) in CD Cl and C (1 mL), respectively. Subsequent removal
of all solvents under full vacuum for 20 h afforded the 3·R PO adducts in
a 1:1 ratio. The products were dissolved in the appropriate deuterated
solvent (0.7 mL). The (C ·R PO complexes were prepared by
mixing (C (9–10 mg) with the indicated phosphine oxide
1.0 equiv) in CD Cl and C (0.7 mL), respectively. All prepared solu-
tions were directly subjected to NMR analysis. See the Supporting Infor-
(
m, 2F, m-C
6
F
5
6 6
D
C
(
1
1
1
6
D
6
2
2
(
6 5
F
epine benzonitrile adduct (3·PhCN): A sample of the crude 3 (70 mg,
.10 mmol, 67% purity) was dissolved in 1,2-C (0.3 mL), and benzo-
0
6 4 2
H F
6
F
5
6 5
F
nitrile (2 drops) was added. The yellow solution was layered with n-
hexane (1 mL) and cooled to ꢀ358C. The title compound was obtained
as colorless crystals. Crystals suitable for X-ray diffraction were obtained
6
F
5
19
carbon atom detected); F NMR (282 MHz, C
), ꢀ158.8 (t, J=20.8 Hz, 1F, p-C
B NMR (96 MHz, C
6 6
D
C
6
F
5
6
F
5
6 5
F
by slow crystallization from a more dilute solution at ꢀ358C. Yield:
11
6
D
6
1
5
5 mg (0.098 mmol, 96%). H NMR (300 MHz, C
6
D
6
): d=2.52 (d, AB
A
H
U
G
R
N
U
G
6 5 3
F ) with the Gutmann–
spin system, J=12.7 Hz, 2H, BCH
2.7 Hz, 2H, BCH ), 6.49–6.56 (m, 2H, PhCN), 6.70–6.80 (m, 3H,
PhCN), 7.02 (ddd, J=8.3 Hz, J=6.8 Hz, J=1.3 Hz, 2H), 7.21 (ddd, J=
2
), 2.59 (d, AB spin system, J=
2
2
6
D
6
3
1
2
(
2
2
6 6
D
8
.1 Hz, J=6.8 Hz, J=1.1 Hz, 2H), 7.52 (d, J=8.3 Hz, 2H), 7.66 (d, J=
.5 Hz, 2H), 7.77 (d, J=8.3 Hz, 2H), 7.81 ppm (d, J=8.1 Hz, 2H);
C NMR (75 MHz, C D ): d=32.4 (br s, BCH ), 107.4 (PhCN), 114.3
6 6 2
3
8
1
3
B
A
H
U
G
R
N
U
G
6
F
5
)
3
3
(
(
PhCN), 124.4, 126.0, 127.4, 127.5, 128.5 (2C), 129.2 (PhCN), 132.6, 132.7
PhCN), 133.4, 133.6, 134.8 (PhCN), 142.4 ppm (signals for carbon atoms
B
A
H
U
G
R
N
U
G
6 5 3
F )
(
2
2
6 6
D
1
9
of C
6
F
5
not resolved); F NMR (282 MHz, C
), ꢀ158.2 (t, J=20.9 Hz, 1F, p-C ), ꢀ163.7 ppm (m, 2F, m-C
B NMR (96 MHz, C ): d=2.2 ppm (br s).
S)-4-(Pentafluorophenyl)-4,5-dihydro-3H-dinaphtho[2,1-c:1’,2’-e]bor-
6
D
6
): d=ꢀ131.6 (m, 2F, o-
1
11
31
C
6
F
5
6
F
5
6
F
5
);
mation for H, B and P NMR data.
1
1
6
D
6
Dehydrogenative Si–O coupling of rac-1-phenylethanol (rac-8) and
MePh SiH (7): A 2 mL vial was charged with 3·THF (5.3 mg, 10 mmol,
(
2
epine triphenylphosphine adduct (3·Ph
3
P): A sample of 3·THF (60 mg,
(1 mL), and Ph
30 mg, 0.11 mmol, 1.0 equiv) was added. All volatiles were removed
5.0 mol%) and 1,2-C H F (0.2 mL) in a glove box. To this, a solution of
6
4 2
0
.11 mmol, 1.0 equiv) was dissolved in 1,2-C
6
H
4
F
2
3
P
MePh SiH (7, 43.0 mg, 0.217 mmol, 1.00 equiv), rac-8 (32.5 mg,
2
(
0.266 mmol, 1.23 equiv) and 1,2-difluorobenzene (0.3 mL) was added,
under vacuum to obtain the title compound as a crystalline solid in quan-
evolution of gas was observed. The vial was loosely closed, and the color-
less solution was maintained at room temperature for 16 h. The crude re-
action mixture was directly subjected to flash column chromatography on
silica gel (cyclohexane/ethyl acetate 40:1), yielding rac-10 as a colorless
liquid. Yield: 59.3 mg (0.186 mmol, 86%). For the analytic data of rac-10,
see below.
1
titative yield. H NMR (300 MHz, C
6
D
6
): d=2.77 (d, AB spin system, J=
), 3.13 (dt, AB spin system, J=13.3 Hz, JH,F =2.5 Hz,
), 6.81–6.89 (m, 6H, Ph P), 6.91–7.02 (m, 5H, Ph P and Np),
.14–7.23 (m, 8H, Ph P and Np), 7.41 (d, J=8.3 Hz, 2H), 7.56 (d, J=
.5 Hz, 2H), 7.62 (d, J=8.3 Hz, 2H), 7.75 ppm (d, J=8.0 Hz, 2H);
1
2
7
8
3.3 Hz, 2H, BCH
2
H, BCH
2
3
3
3
1
3
C NMR (100 MHz, C
27.6, 128.4, 128.9 (d, J=8.6 Hz), 130.7, 132.4, 133.3, 133.8, 134.3 (d, J=
1.5 Hz), 137.6 (dm, J=250 Hz, m-C ), 139.6 (dm, J=250 Hz, p-C ),
42.7, 149.9 ppm (dm, J=240 Hz, o-C ) (not all signals were clearly re-
): d=ꢀ123.6 (m, 2F, o-C ), ꢀ157.0
), ꢀ163.6 ppm (m, 2F, m-C ); B NMR
6
D
6
): d=29.5 (br s, BCH
2
), 124.3, 125.8, 127.6,
Hydrosilylation of acetophenone (9) with MePh SiH (7): A 2 mL vial
2
1
1
1
was charged with MePh SiH (7, 68.2 mg, 0.344 mmol, 1.06 equiv) and 9
2
6
F
5
6
F
5
(39.1 mg, 0.325 mmol, 1.00 equiv) in a glove box. To this mixture, 3·THF
6
F
5
(5.3 mg, 10 mmol, 3.1 mol%) was added, resulting in a color change to
lemon yellow. The vial was closed, and the solution was maintained at
room temperature for 16 h. The crude reaction mixture was directly sub-
1
9
solved); F NMR (282 MHz, C
t, J=21.6 Hz, 1F, p-C
6
D
6
6 5
F
1
1
(
6
F
5
6 5
F
9412
ꢃ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Eur. J. 2011, 17, 9406 – 9414