M. Saito, S. Imaizumi, T. Tajima
FULL PAPER
ene, 373 K): δ = 55.55 (q), 115.47 (d, JSn,C = 60 Hz), 125.42 (s),
0.57 mL, 0.81 mmol) at –78 °C, and the resulting mixture was
127.93 (d, JSn,C = 24 Hz), 128.05 (d, JSn,C = 60 Hz), 129.24 (d, JSn,C stirred for 15 min at the same temperature. To the mixture was
= 11 Hz), 129.69 (d), 131.96 (d, JSn,C = 41 Hz), 132.81 (d), 133.95
(d), 138.37 (s), 139.21 (d, JSn,C = 47 Hz), 139.45 (d, JSn,C = 156 Hz),
added
a THF (1 mL) solution of dichlorodimethylstannane
(45.5 mg, 0.21 mmol), and the reaction mixture was warmed to
141.91 (s), 146.03 (s, JSn,C = 18 Hz), 150.62 (s, JSn,C = 33 Hz), room temperature. After concentration of the filtrate, the residue
161.65 (s) ppm. 119Sn NMR ([D8]toluene, 373 K): δ = –122.37 ppm.
C38H30Br2O2Sn (797.18): calcd. C 57.25, H 3.79; found C 57.33, H
3.65.
was recrystallized from dichloromethane and ethanol to afford 9-
(2-biphenyl)-9-methyl-9-stannafluorene (2b; 21.3 mg, 25%). M.p.
131–132 °C (dichloromethane/methanol). 1H NMR (CDCl3): δ =
0.11 (s, JSn,H = 61, 63 Hz, 3 H), 7.26–7.33 (m, 3 H), 7.37–7.46 (m,
6 H), 7.46–7.62 (m, 6 H), 7.93–7.98 (m, 2 H) ppm. 13C NMR
(CDCl3): δ = –8.03 (q, JSn,C = 397 Hz), 122.64 (d, JSn,C = 40 Hz),
126.95 (d, JSn,C = 53 Hz), 127.59 (d, JSn,C = 43 Hz), 127.61 (d),
Bis(2-bromo-2Ј-biphenyl)stannane (1b): To a THF (15 mL) solution
of 1,2-dibromobenzene (0.66 mL, 5.47 mmol) was added butyllith-
ium (1.60 in hexane, 3.6 mL, 5.76 mmol) at –78 °C, and the re-
sulting mixture was stirred at the same temperature for 1 h. To the
mixture was added a THF (2 mL) solution of dichlorodimethyl-
stannane (303.9 mg, 1.38 mmol), and the reaction mixture was
warmed to room temperature. After removal of the volatile sub-
stances, materials insoluble in dichloromethane were filtered off.
After concentration of the filtrate, the residue was recrystallized
from dichloromethane and ethanol to afford 1b (390.1 mg, 47%).
M.p. 112–113 °C (dichloromethane/methanol). 1H NMR ([D8]tolu-
ene, 373 K): δ = –0.34–0.16 (m, 6 H), 6.76–6.80 (m, 2 H), 6.87–
6.91 (m, 2 H), 6.98–6.99 (m, 2 H), 7.10–7.17 (m, 6 H), 7.27–7.45
(m, 4 H) ppm. 13C NMR ([D8]toluene, 373 K): δ = –7.18 (q), 125.39
128.63 (d), 128.65 (d), 128.74 (d), 128.81 (d), 129.09 (d, JSn,C
=
11 Hz), 129.28 (d, JSn,C = 9 Hz), 136.15 (d, JSn,C = 41 Hz), 137.19
(d, JSn,C = 40 Hz), 138.29 (d), 140.54 (s), 145.79 (s, JSn,C = 21 Hz),
148.26 (s), 149.91 (s) ppm. 119Sn NMR (CDCl3): δ = –105.93 ppm.
C25H30Sn (449.25): calcd. C 68.38, H 4.59; found C 68.10,
H 4.43.
Reaction of 1a with tert-Butyllithium: To a THF (4 mL) solution of
1a (113.6 mg, 0.14 mmol) was added tert-butyllithium (1.42 in
pentane, 0.40 mL, 0.57 mmol) at –78 °C, and the reaction mixture
was warmed to room temperature. After removal of the volatile
substances, the residue was subjected to WCC (hexane/ethyl acet-
ate, 5:1) to afford 2a (49.5 mg, 65%) and 9,9-bis(p-methoxyphenyl)-
9-stannafluorene[11] (5a; 10.3 mg, 15%).
(s), 127.84 (d), 127.96 (d, JSn,C = 34, 37 Hz), 128.92 (d, JSn,C
11 Hz), 129.62 (d), 130.74 (d, JSn,C = 37 Hz), 132.77 (d, JSn,C
=
=
137 Hz), 133.74 (d, JSn,C = 17 Hz), 137.91 (d), 142.92 (s), 146.37
(s, JSn,C = 20 Hz), 150.20 (s, JSn,C = 29 Hz) ppm. 119Sn NMR ([D8]-
toluene, 373 K): δ = –58.81, –57.04 ppm. C26H22Br2Sn (612.98):
calcd. C 50.95, H 3.62; found C 50.90, H 3.46.
Reaction of 1b with tert-Butyllithium: To a THF (5 mL) solution of
1b (117.8 mg, 0.19 mmol) was added tert-butyllithium (1.76 in
pentane, 0.50 mL, 0.88 mmol) at –78 °C, and the reaction mixture
was warmed to room temperature. After removal of the volatile
substances, materials insoluble in dichloromethane were removed
by filtration. The residue was subjected to PTLC (hexane) to afford
2b (49.6 mg, 58%).
Reaction of 1a with tert-Butyllithium Quenched by Dichloro[bis(p-
methoxyphenyl)]stannane: To a THF (10 mL) solution of 1a
(506.4 mg, 0.64 mmol) was added tert-butyllithium (1.42 in pen-
tane, 1.80 mL, 2.55 mmol) at –78 °C, and the resulting mixture was
stirred for 15 min at the same temperature. To the mixture was
added a THF (2 mL) solution of dichloro[bis(p-methoxyphenyl)]-
stannane[9] (276.1 mg, 0.68 mmol), and the reaction mixture was
warmed to room temperature. After removal of the volatile sub-
stances, the residue was subjected to WCC (hexane/ethyl acetate,
5:1) to afford 9-(2-biphenyl)-9-p-methoxyphenyl-9-stannafluorene
(2a; 86.8 mg, 25%), spirostannafluorene[10] 3 (48.2 mg, 18%), and
tetrakis(p-methoxyphenyl)stannane[9] (4; 100.2 mg, 29%). Data for
2a: M.p. 112 °C (dichloromethane/methanol). 1H NMR (CDCl3):
δ = 3.73 (s, 3 H), 6.71–6.77 (m, 2 H), 7.03–7.18 (m, 2 H), 7.24–7.28
(m, 2 H), 7.30–7.47 (m, 12 H), 7.18–7.27 (m, 4 H), 7.62–7.89 (m,
Monitoring the Reaction of 1a with tert-Butyllithium by 119Sn NMR
Spectroscopy: In an NMR tube, to a THF (0.4 mL) solution of
1a (49.7 mg, 0.062 mmol) was added tert-butyllithium (1.46 in
pentane, 0.17 mL, 0.25 mmol) at –78 °C and C6D6 (0.20 mL). The
119Sn NMR spectrum of the reaction mixture at 213 K revealed
the formation of pentaorganostannate 7a. 119Sn NMR (THF/C6D6,
213 K): δ = –268.28 ppm.
Monitoring the Reaction of 1b with tert-Butyllithium by 119Sn NMR
Spectroscopy: In an NMR tube, to a THF (0.4 mL) solution of
1b (35.8 mg, 0.058 mmol) was added tert-butyllithium (1.46 in
pentane, 0.16 mL, 0.23 mmol) at –78 °C and C6D6 (0.20 mL). The
119Sn NMR spectrum of the reaction mixture at 213 K revealed the
formation of pentaorganostannate 7b.[4] 119Sn NMR (THF/C6D6,
213 K): δ = –252.88 ppm.
4 H) ppm. 13C NMR(CDCl3): δ = 54.96 (q), 114.26 (d, JSn,C
=
63 Hz), 122.72 (d, JSn,C = 42 Hz), 127.03 (d, JSn,C = 55 Hz), 127.50
(d), 127.67 (d, JSn,C = 43 Hz), 128.67 (d), 128.68 (d), 128.79 (d),
129.31 (d, JSn,C = 45 Hz), 129.34 (s), 129.38 (s, JSn,C = 8 Hz), 136.28
(d, JSn,C = 40 Hz), 137.45 (d, JSn,C = 48 Hz), 137.61 (s), 139.09 (s),
139.64 (s), 145.56 (s, JSn,C = 20 Hz), 147.85 (s, JSn,C = 74 Hz),
150.08 (s), 160.31 (s) ppm. 119Sn NMR(CDCl3): δ = –65.99 ppm.
C31H24OSn (531.25): calcd. C 70.09, H 4.55; found C 69.95, H
4.40. Data for 3: M.p. 216–218 °C (dichloromethane/methanol). 1H
NMR (CDCl3): δ = 7.26–7.34 (m, 4 H), 7.47–7.51 (m, 4 H), 7.53–
7.66 (m, 4 H), 8.06–8.11 (m, 4 H) ppm. 13C NMR (CDCl3): δ =
122.85 (d, JSn,C = 47 Hz), 128.29 (d, JSn,C = 49 Hz), 130.16 (d, JSn,C
= 9 Hz), 135.96 (s, JSn,C = 501, 524 Hz), 137.03 (d, JSn,C = 48 Hz),
148.10 (s, JSn,C = 80 Hz) ppm. 119Sn NMR (CDCl3): δ =
–67.43 ppm. C24H16Sn (423.1): calcd. C 68.13, H 3.81; found C
67.99, H 3.72.
Monitoring the Reaction of 9-Stannafluorene 5b with Methyllithium
by 119Sn NMR Spectroscopy: In an NMR tube, to a THF (0.3 mL)
solution of 5b (94.5 mg, 0.31 mmol) was added methyllithium
(0.98 in ethyl ether, 0.32 mL, 0.31 mmol) at –78 °C and C6D6
(0.20 mL). The 119Sn NMR spectrum of the reaction mixture at
213 K revealed the formation of pentaorganostannate 8b. 1H NMR
(THF, Et2O/C6D6, 213 K): δ = 0.01 (s, JSn,H = 40 Hz, 9 H), 6.93–
7.10 (m, 4 H), 7.70–7.86 (m, 4 H) ppm. 13C NMR (THF, Et2O/
C6D6, 213 K): δ = 0.55 (q, JSn,C = 295, 303 Hz), 119.09 (d, JSn,C
=
31 Hz), 124.92 (d), 125.20 (d), 136.17 (d, JSn,C = 42 Hz), 144.68 (s,
Reaction of 1b with tert-Butyllithium Quenched by Dichlorodi- JSn,C = 68 Hz), 165.01 (s, JSn,C = 308, 323 Hz) ppm. 119Sn NMR
methylstannane: To a THF (10 mL) solution of 1b (121.3 mg,
0.20 mmol) was added tert-butyllithium (1.42 in pentane,
(THF, Et2O/C6D6, 213 K): δ = –263.77 ppm. 7Li NMR (THF,
Et2O/C6D6, 213 K): δ = –0.20 ppm.
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Eur. J. Inorg. Chem. 2010, 2153–2157