1678 J. Am. Chem. Soc., Vol. 120, No. 8, 1998
Takahashi et al.
1
6
4.29, 14.50, 15.80, 15.87, 16.03, 16.39, 21.80, 22.25, 22.50, 24.10,
0.77, 129.43, 134.01, 135.43, 137.93, 138.79, 141.26, 171.53; HRMS
(s, 18H), 1.55-1.65 (m, 4H), 1.75-1.85 (m, 2H), 2.95-3.05 (m, 4H),
3.80 (s, 6H); 13C NMR δ 2.03(6C), 28.01(2C), 31.48, 35.06(2C), 52.24-
calcd for C18
H
28
O
2
276.2089, found 276.2084.
3
(2C), 135.74(2C), 136.91(2C), 151.50(2C), 170.80(2C). IR (CDCl )
-1
Ethyl 2-Phenyl-3,4,5,6-tetraethylbenzene Carboxylate (3c). GC
yield 92%. Isolated yield (193 mg) 57%. H NMR (CDCl
2 4
1730, 1265, 1151, 848 cm . Anal. Calcd for C20H32Si O : C, 62.02;
1
3
, Me
4
Si) δ
H, 8.43. Found: C, 62.06; H, 8.47.
0
3
7
.89 (t, J ) 7.3 Hz, 3H), 0.91 (t, J ) 7.6 Hz, 3H), 1.20 (t, J ) 7.6 Hz,
Dimethyl 3,4-Diethylnaphthalene-1,2-dicarboxylate (5e). GC
yield 80%. Isolated yield (204 mg) 54%. 1H NMR (CDCl
, Me Si) δ
1.26 (t, J ) 7.6 Hz, 3H), 1.28 (t, J ) 7.6 Hz, 3H), 2.85 (q, J ) 7.6 Hz,
2H), 3.15(q, J ) 7.6 Hz, 2H), 3.92 (s, 3H), 3.97 (s, 3H), 7.45-760
(m, 2H), 8.05-8.10 (m, 1H), 8.13-8.18 (m, 1H); 13C NMR δ 15.20,
15.79, 21.67, 24.04, 52.45, 52.58, 124.20, 126.45, 126.56, 127.40,
H), 1.21 (t, J ) 7.6 Hz, 3H), 1.22 (t, J ) 7.3 Hz, 3H), 2.44 (q, J )
.6 Hz, 2H), 2.63 (q, J ) 7.6 Hz, 2H), 2.72 (q, J ) 7.6 Hz, 4H), 3.84
3
4
1
3
(q, J ) 7.3 Hz, 2H), 7.20-7.40 (m, 5H); C NMR (CDCl
3
, Me
4
Si) δ
1
1
1
3.68, 15.62, 15.76, 15.81, 16.01, 21.88, 22.23, 22.95, 23.92, 60.39,
26.84, 127.44 (2C), 130.11(2C), 133.62, 135.36, 136.98, 138.24,
39.71, 139.96, 141.44, 170.40; IR (neat) 2973, 2934, 1726, 1277, 1182
127.96, 128.61, 132.45, 132.61, 134.86, 141.77, 168.44, 169.68; IR
-
1
-1
cm ; HRMS calcd for C23
H O
30 2
338.2246, found 338.2250.
(CDCl
HRMS calcd for C18H O
3
solution) 2972, 1734, 1435, 1271, 1226, 1201, 1163 cm
300.1362, found: 300.1356.
.
2
,3,4,5-Tetraethyl-6-phenyl Benzonitrile (3d). GC yield 97%.
20 4
1
Isolated yield 70%. H NMR (CDCl
3
, Me
4
Si): δ 0.92 (t, J ) 7.5 Hz,
Reaction of 1a with 2 in the Presence of Other Metal Halides
Instead of CuCl. The reaction procedure was essentially the same as
that described above when CuCl was used. Commercially available
metal halides were used without further purification. When CuCl2,
SnCl , and SnCl were used, 3a was formed in 28%, 26%, and 30%
3
4
Me
1
1
H), 1.20-1.31 (m, 9H), 2.46 (q, J ) 7.5 Hz, 2H), 2.72-2.78 (m,
H), 2.92 (q, J ) 7.5 Hz, 2H), 7.26-7.46 (m, 5H). 1 C NMR (CDCl
Si) δ 15.38 (2x), 15.50, 15.57, 22.07, 22.51, 23.03, 25.11, 111.88,
17.99, 127.75, 128.19, 129.17, 139.09, 139.33, 140.17, 143.56, 144.05,
45.62. HRMS calcd for C21 25N 291.1986, found, 291.1991.
,3,4,5-Tetraethyl-6-phenyl N,N-Dimethyl Benzamide (3e). GC
3
3
,
4
2
4
H
yields, respectively, though GC analysis showed that hydrolysis
compound of 1a almost completely disappeared. Use of CoBr and
BiCl afforded 3a in 15% and 35% yields, respectively. In the case of
CoBr , 47% of 1a remained unreacted, while 36% of 1a was recovered
in the case of BiCl
2
2
1
yield 82%. Isolated yield 55%. H NMR (CDCl
3
, Me
4
Si): δ 0.88 (t,
3
J ) 7.5 Hz, 3H), 1.16-1.24 (m, 9H), 2.38-2.55 (m, 4H), 2.59 (s,
2
3
H), 2.60 (s, 3H), 2.70-2.76 (m, 4H), 7.16-7.35 (m, 5H). 13C NMR
3
.
(CDCl , Me Si) δ 15.35, 15.37, 15.62, 15.73, 21.71, 21.96, 22.65, 23.39,
3
4
A Representative Procedure for One-Pot Preparation of Benzene
Derivatives from Three Different Alkynes: Dimethyl 3,4-Dibutyl-
5,6-diethylbenzene-1,2-dicarboxylate (3k). A 50 mL Schlenk tube
under dried nitrogen was charged with Cp ZrCl (2.5 mmol, 730 mg)
3
3.39, 38.37, 126.48, 126.54, 127.70, 128.67, 130.57, 134.85, 135.07,
1
35.92, 138.05, 139.42, 139.87, 140.50, 170.96. HRMS calcd for
C
23
H31ON 337.2404, found 337.2405.
2
2
3
,4,5,6-Tetraethyl-1,2-dibenzophenone (3f). GC yield 57%. Iso-
and THF (20 mL). The mixture was cooled to -78 °C (dry
ice/methanol bath), and then 1.7 M n-BuLi (5 mmol, 2.94 mL) was
added dropwise via a syringe. The reaction mixture was stirred at -78
°C for 1 h under nitrogen, ethylene gas was introduced for 1 h, and the
reaction mixture was gradually warmed to room temperature. The
reaction mixture changed from light yellow to yellow-brown. 5-Decyne
(2 mmol, 0.36 mL) was added, and the resulting mixture was stirred
for 1 h at room temperature under a positive pressure of ethylene gas.
After 3-hexyne (2 mmol, 0.23 mL) was added, the mixture was heated
1
lated yield 48%. H NMR (CDCl
H), 1.25 (t, J ) 7.5 Hz, 6H), 2.50 (q, J ) 7.4 Hz, 4H), 2.78 (q, J )
3
, Me
4
Si): δ 1.02 (t, J ) 7.5 Hz,
6
7
1
1
1
3
.5 Hz, 4H), 7.26-7.65 (m, 10H). C NMR (CDCl
5.86, 21.72, 23.36, 127.97, 129.81, 133.05, 136.23, 136.77, 137.85,
41.91, 199.13. HRMS calcd for C28 398.2244, found 398.2257.
,3,4,5-Tetraethyl-6-butyl Benzophenone (3g). GC yield 54%.
3 4
, Me Si) δ 15.71,
30 2
H O
2
1
Isolated yield 28%. H NMR (CDCl
.22-2.75 (m, 8H), 7.39-7.81 (m, 5H). C NMR (CDCl , Me Si) δ
3 4
3.57, 15.85, 15.90, 15.93, 15.97, 21.54, 21.62, 22.14, 23.23, 23.74,
0.63, 33.85, 128.35, 129.43, 133.12, 134.54, 135.63, 138.06, 138.13,
38.18, 138.31, 141.01, 201.12. HRMS calcd for C25H34O 350.2608,
3
, Me
4
1
Si): δ 0.75-1.27 (m, 21H),
3
2
1
3
1
2
at 50 °C under an atmosphere of dry N instead of ethylene gas and
was stirred for 1 h. Then, to the above reaction solution containing
zirconacyclopentadiene 1k were added dimethyl acetylenedicarboxylate
2 (568 mg, 4 mmol) and copper(I) chloride (396 mg, 4 mmol) at 0 °C.
After stirring for 1 h at room temperature, the reaction mixture was
quenched with 3 N HCl and extracted with diethyl ether. The extract
found 350.2602.
,3,4,5-Tetraethyl-6-phenyl 4′-Nitrobenzophenone (3h). NMR
2
1
yield 64%. Isolated yield 42%. H NMR (CDCl
J ) 7.4 Hz, 3H), 1.11 (t, J ) 7.5 Hz, 3H), 1.26-1.31 (m, 6H), 2.77-
.83 (m, 8H), 7.02-7.06 (m, 5H), 7.59 (d, J ) 8.6 Hz, 2H), 8.06 (d,
3 4
, Me Si): δ 0.92 (t,
was then washed with water, NaHCO
over MgSO . The solvent was evaporated in vacuo to give a light
brown oil. Column chromatography on silica gel (4/1 hexane/Et O)
afforded 510 mg of 3k (71% isolated yield). GC yield 90%. H NMR
(CDCl , Me Si) δ 0.90-1.00 (m, 6H), 1.12-1.22 (m, 6H), 1.33-1.56
(m, 8H), 2.59-2.73 (m, 8H), 3.83 (s, 3H), 3.84 (s, 3H); C NMR
(CDCl , Me Si) δ 13.84 (2C), 15.49, 15.98, 22.19, 23.32, 23.47, 23.52,
3
, brine, and water and then dried
2
4
1
3
J ) 8.6 Hz, 2H). C NMR (CDCl
3
, Me
6.19, 21.77, 22.33, 22.59, 23.58, 123.06, 126.76, 127.30, 129.72,
31.00, 136.13, 136.91, 137.25, 138.38, 138.71, 140.27, 142.19, 143.21,
49.68, 198.90. HRMS calcd for C27 N 415.2146, found 415.2132.
Dimethyl 1,4-Dimethylbenzocyclobutene-2,3-dicarboxylate (5a).
4
Si) δ 15.58, 15.78, 15.85,
2
1
1
1
1
3
4
1
3
29 3
H O
3
4
1
GC yield 73%. Isolated yield (283 mg) 57%. H NMR (CDCl
Si) δ 2.20 (s, 6H), 3.05 (s, 4H), 3.84 (s, 6H); C NMR (CDCl
Si) δ 14.32, 27.22, 52.16, 129.04, 131.14, 147.13, 169.13; HRMS calcd
for C14 248.1049, found 248.1047.
Dimethyl 1,4-Diethyl-5,6,7,8-tetrahydronaphthalene-2,3-dicar-
boxylate (5b). GC yield 93%. Isolated yield (390 mg) 64%. mp 109-
10 °C. H NMR (CDCl
.81 (m, 4H), 2.65 (q, J ) 7.2 Hz, 4H), 2.76 (t, J ) 6.6 Hz, 4H), 3.84
s, 6H); C NMR δ 14.61, 22.57, 23.20, 26.79, 52.15, 129.56, 138.15,
38.45, 169.63; IR (CDCl
069 cm ; HRMS calcd for C18 304.1675, found 304.1662.
Dimethyl 1,4-Bis(trimethylsilyl)-5,6,7,8-tetrahydronaphthalene-
,3-dicarboxylate (5c). GC yield 85%. Isolated yield (552 mg) 70%.
3
, Me
, Me
4
-
-
29.07, 30.26, 33.49, 33.94, 52.15 (2C), 130.42, 130.47, 137.14, 137.97,
1
3
3
4
142.15, 143.29, 169.75 (2C); IR (neat) 2959, 1730, 1458, 1294, 1204,
-
1
34 4
1177 cm ; HRMS calcd for C22H O 362.2460, found 362.2466.
H O
16 4
Dimethyl 3,4-Diethyl-5,6-diphenylbenzene-1,2-dicarboxylate (3i).
1
GC yield 95%. Isolated yield (507 mg) 63%. Mp 162-163 °C; H
3 4
NMR (CDCl , Me Si) δ 0.95 (t, J ) 7.3 Hz, 3H), 1.28 (t, J ) 7.3 Hz,
1
1
1
(
1
3
, Me
4
Si) δ 1.15 (t, J ) 7.6 Hz, 6H), 1.76-
3H), 2.53 (q, J ) 7.3 Hz, 2H), 2.85 (q, J ) 7.6 Hz, 2H), 3.40 (s, 3H),
3.89 (s, 3H), 6.9-7.15 (m, 10H); 13C NMR (CDCl
, Me Si) δ 15.29,
3
4
1
3
15.94, 23.40, 23.49, 51.97, 52.45, 126.41, 126.56, 127.07(2C), 127.40-
(2C), 129.72(2C), 130.03(2C), 130.58, 131.71, 138.36, 139.10, 139.35,
3
solution) 2948, 1734, 1458, 1285, 1206,
-
1
1
H O
24 4
139.60, 143.56, 143.99, 168.96, 169.38; IR (CDCl
1734, 1439, 1333, 1215 cm . HRMS calcd for C26
found 402.1841.
3
solution) 2974,
26 4
H O 402.1831,
-
1
2
1
Mp 146-147 °C; H NMR (CDCl
3
, Me
4
Si) δ 0.32 (s, 18H), 1.65-
Dimethyl 1-Trimethylsilyl-4,5-diphenyl-6-methylbenzene-2,3-di-
13
1
1
3
1
3
.75 (m, 4H), 2.75-2.80 (m, 4H), 3.81 (s, 6H); C NMR δ 1.69, 20.70,
carboxylate (3j). Isolated yield (250 mg) 56%. Mp 160-161 °C; H
0.42, 52.24, 135.42, 136.15, 147.58, 170.80; IR(CDCl
3
) 2951, 1732,
NMR (CDCl
3 4
, Me Si) δ 0.39 (s, 9H), 2.21 (s, 3H), 3.41 (s, 3H), 3.85
283, 1253, 1155 cm-1; HRMS calcd for C20
92.1843.
H32Si O
2 4
392.1839, found
13
(s, 3H), 6.88-7.16 (m, 10H); C NMR (CDCl , Me Si) δ 1.63 (3C),
3 4
23.91, 51.99, 52.46, 126.58, 126.65, 127.19 (2C), 127.82 (2C), 129.46
(2C), 129.80 (2C), 130.72, 137.24, 137.71, 138.74, 139.65, 139.92,
Dimethyl 6,7,8,9-Tetrahydro-1,4-bis(trimethylsilyl)-5H-benzocy-
clo-heptene-2,3-dicarboxylate (5d). GC yield 85%. Isolated yield
544 mg) 67%. Mp 137-138 °C. H NMR (CDCl
-1
143.54, 145.09, 169.38, 170.11; IR (neat) 2951, 1734, 1443, 1395 cm
HRMS (EI) calcd for C26 Si 432.1757, found 432.1758.
;
1
(
3
, Me
4
Si) δ 0.30
28 4
H O