Monocarbenepalladium(0) Complexes
3901±3906
À1
1
7
40, 691 cm ; MS (FAB): m/z (%): 1038 (5) [M] , 822 (100), 714 (62);
4-Methoxystilbene: H NMR (400 MHz, CDCl
3
, 238C): d 3.83 (s, 3H),
3
3
elemental analysis calcd (%) for C54
.39; found: C 62.75, H 5.42, N 5.30.
H
56
N
4
O
4
Pd
2
(1037.9): C 62.49, H 5.44, N
6.90 (d, J(H,H) 8.5 Hz, 2H), 6.97 (d, J(H,H) 16.2 Hz, 1H), 7.06 (d,
3
3
5
J(H,H) 16.2 Hz, 1H), 7.23 ± 7.36 (m, 3H), 7.45 (d, J(H,H) 8.7 Hz, 2H),
3
13
7
.48 ppm (d, J(H,H) 7.5 Hz, 2H); C NMR (100 MHz, CDCl
3
, 238C):
Synthesis of [(1,3-dimesitylimidazol-2-ylidene)(naphthoquinone)palladi-
um(0)] (3): Complex 3 was prepared similar to 2 from (1,5-cyclooctadie-
ne)(naphthoquinone)palladium(0) (372.5 mg, 1 mmol). Yield: 480 mg,
4%; 1H NMR (400 MHz, [D
), 2.09
s, 12H; CH ), 3.34 (s, 12H; CH
), 3.88 (d, J(H,H) 6.5 Hz, 2H; nq-CH),
.94 (d, J(H,H) 6.5 Hz, 2H; nq-CH), 6.84 (s, 8H; aryl-CH), 7.15 (m, 4H;
d 55.8, 114.6, 126.7, 127.0, 127.6, 128.1, 128.6, 129.1, 130.6, 138.1,
2
1
59.7 ppm; MS (70 eV): m/z (%): 210 (100) [M] .
1
8
(
3
8
]THF, 238C): d 1.85 (s, 12H; CH
3
4-N,N-Diethylaminostilbene:
(m, 6H), 3.29 (m, 4H), 6.59 (d,
16.3 Hz, 1H), 6.36 (d,
2H), 7.31 (d,
H NMR (400 MHz, CDCl , 238C): d 1.09
3
3
3
J(H,H) 8.5 Hz, 2H), 6.81 (d, J(H,H)
3
3
3
3
3
J(H,H) 16.3 Hz, 1H), 6.99 ± 7.19 (m, 3H), 7.24 (m,
3
3
J(H,H) 8.9 Hz, 2H), 7.39 ppm (m, 2H); MS (70 eV): m/z
aryl-CH), 7.17 (s, 4H; imidazole-CH), 7.34 (d, J(H,H) 7.3 Hz, 2H; aryl-
3
13
(%): 251 (66) [M] , 236 (100).
CH), 7.37 ppm (d, J(H,H) 7.5 Hz, 2H; aryl-CH); C NMR (100 MHz,
), 19.1 (CH ), 19.5 (CH ), 56.2 (nq-CH), 72.1
nq-CH), 124.7 (CH), 125.9 (CH), 126.9 (CH), 130.1 (CH), 130.3 (CH),
1
3
[
D
8
]THF, 238C): d 19.0 (CH
3
3
3
4-Nitrostilbene: H NMR (400 MHz, CDCl , 238C): d 7.14 (d, J(H,H)
3
3
(
16.2 Hz, 1H), 7.25 ± 7.42 (m, 4H), 7.55 (d, J(H,H) 7.4 Hz, 2H), 7.63 (d,
1
1
8
30.9 (CH), 131.6 (CH), 136.0, 137.8, 138.1, 139.1, 139.8, 140.9, 170.4, 184.3,
3
J(H,H) 8.7 Hz, 2H), 8.22 ppm (d,
3
J(H,H) 8.7 Hz, 2H); 13C NM R
92.9 ppm; IR (KBr): nÄ 3448, 1632, 1577, 1530, 1488, 1319, 1298, 1009,
(100 MHz, CDCl , 238C): d 123.1, 125.2, 125.8, 126.0, 127.8, 127.9, 132.3,
3
À1
50, 783 cm ; MS (FAB): m/z (%): 1138 (3) [M] , 821 (100), 714 (30);
135.1, 142.8, 145.7 ppm; MS (70 eV): m/z (%): 225 (100) [M] .
elemental analysis calcd (%) for C62
H
60
N
4
O
4
Pd
2
(1137.6): C 65.44, H 5.31, N
-Bromostilbene: 1H NMR (400 MHz, CDCl
4
3
,
238C): d 6.96 (d,
4
.92; found: C 65.79, H 5.48, N 4.80.
3
3
J(H,H) 16.3 Hz, 1H), 7.03 (d, J(H,H) 16.3 Hz, 1H), 7.20 (m, 1H),
1
3
General procedure for Heck and Suzuki reactions: Aryldiazonium salts
7.28 (m, 4H), 7.42 ppm (m, 4H); C NMR (100 MHz, CDCl
3
, 238C): d
(
(
1.0 mmol), olefin (1.5 mmol) or arylboronic acid (1.5 mmol), and 3
5.7 mg, 0.005 mmol, 1 mol% Pd) were charged in a Schlenk tube under
121.8, 127.0, 127.8, 128.3, 128.4, 129.2, 129.9, 132.2, 136.7, 137.8 ppm; MS
(70 eV): m/z (%): 260 (56) [M] , 258 (54), 179 (93), 178 (100).
argon. Methanol (5 mL) was syringed in and the solution was stirred at
08C for 1 h. Diethyleneglycol di-n-butyl ether (200 mL) was added as
internal standard and the yield was determined by GC. After the organic
phase had been washed with water and brine, the solvent was evaporated.
The product was isolated by column chromatography (silica gel, hexane/
ethyl acetate mixtures).
1
4
-N,N-Diethylaminobiphenyl: H NMR (400 MHz, CDCl
3
, 238C): d 1.20
5
3
3
(
t, J(H,H) 6.9 Hz, 6H), 3.40 (q, J(H,H) 6.9 Hz, 4H), 6.75 (d,
3
3
J(H,H) 8.7 Hz, 2H), 7.24 (m, 1H), 7.39 (t, J(H,H) 7.5 Hz, 2H), 7.48
3
3
13
(
(
d, J(H,H) 8.7 Hz, 2H), 7.55 ppm (d, J(H,H) 7.7, 2 H) ; C NM R
100 MHz, CDCl
3
, 238C): d 13.1, 44.9, 112.4, 126.2, 126.6, 128.4, 128.5,
1
29.1, 141.8, 147.6 ppm; MS (70 eV): m/z (%): 225 (59) [M] , 210 (100).
4-N,N-Diethylamino-2'-methylbiphenyl: 1H NMR (400 MHz, CDCl3,
Analytical data of coupling products
3
3
'-Ethylhexyl 4-methoxycinnamate: 1H NMR (400 MHz, CDCl
238C): d 1.13 (t, J(H,H) 6.9 Hz, 6H), 2.25 (s, 3H), 3.31 (q, J(H,H)
2
3
, 238C):
3
7
.1 Hz, 4H), 6.64 (d, J(H,H) 8.7 Hz, 2H), 7.11 ± 7.18 ppm (m, 6H);
d 0.91 (m, 6H), 1.32 ± 1.58 (m, 9H), 3.84 (s, 3H), 4.11 (m, 2H), 6.31 (d,
1
3
3
3
3
C NMR (100 MHz, CDCl , 238C): d 13.1, 21.2, 44.8, 111.6, 126.2, 126.8,
J(H,H) 15.9 Hz, 1H), 6.89 (d, J(H,H) 8.7 Hz, 2H), 7.47 (d, J(H,H)
3
3
13
129.2, 130.4, 130.6, 130.7, 135.9, 142.5, 147.1 ppm; MS (70 eV): m/z (%): 239
8
.7 Hz, 2H), 7.62 ppm (d, J(H,H) 16.1 Hz, 1H); C NMR (100 MHz,
, 238C): d 11.5, 14.5, 23.4, 24.3, 29.4, 30.9, 39.3, 55.8, 67.2, 114.7,
16.2, 127.6, 130.1, 144.6, 161.7, 168.0 ppm; MS (70 eV): m/z (%): 290 (23)
(
56) [M] , 224 (100).
CDCl
1
[
3
4-N,N-Diethylamino-3'-ethoxybiphenyl: 1H NMR (400 MHz, CDCl
,
3
3
3
M] , 178 (100).
238C): d 1.12 (t, J(H,H) 6.9 Hz, 6H), 1.36 (t, J(H,H) 6.9 Hz, 3H),
3
3
1
3.31 (q, J(H,H) 6.9 Hz, 4H), 4.00 (q, J(H,H) 6.9 Hz, 2H), 6.65 (d,
3 4
2
2
3
1
3
'-Ethylhexyl 4-N,N-diethylaminocinnamate: H NMR (400 MHz, CDCl ,
3
3
J(H,H) 8.9 Hz, 2H), 6.70 (dd, J(H,H) 8.1 Hz, J(H,H) 2.2 Hz, 1H),
4 3
38C): d 0.82 (m, 6H), 1.11 (t, J(H,H) 6.9 Hz, 6H), 1.15 ± 1.58 (m, 9H),
3
3
7.02 (d, J(H,H) 1.9 Hz, 1H), 7.05 (d, J(H,H) 7.7 Hz, 1H), 7.20 (dd,
3 3 3
.32 (q, J(H,H) 6.9 Hz, 4H), 4.02 (m, 2H), 6.12 (d, J(H,H) 15.9 Hz,
3
3
J(H,H) 5.9 Hz, J(H,H) 6.5 Hz, 1H), 7.40 ppm (d, J(H,H) 8.9 Hz,
H), 6.55 (d, J(H,H) 8.9 Hz, 2H), 7.32 (d, J(H,H) 8.9 Hz, 2H),
13
3
13
2H); C NMR (100 MHz, CDCl
1
m/z (%): 269 (61) [M] , 254 (100).
3
, 238C): d 13.1, 15.4, 44.8, 63.8, 112.2,
7
.52 ppm (d, J(H,H) 15.7 Hz, 1H); C NMR (100 MHz, CDCl
3
, 238C):
12.3, 112.9, 119.1, 128.3, 128.4, 130.0, 143.3, 147.7, 159.7 ppm; MS (70 eV):
d 11.5, 13.0, 14.5, 23.4, 24.3, 29.4, 30.9, 39.3, 44.9, 67.0, 111.6, 112.4, 121.8,
1
30.4, 145.5, 149.7, 168.7 ppm; MS (70 eV): m/z (%): 331 (60) [M] , 316
4-N,N-Diethylamino-4'-bromobiphenyl: 1H NMR (400 MHz, CDCl
,
(
100).
3
3
3
2
6
38C): d 1.20 (t, J(H,H) 7.2 Hz, 6H), 3.33 (q, J(H,H) 6.9 Hz, 4H),
2
0
1
'-Ethylhexyl 4-nitrocinnamate: 1H NMR (400 MHz, CDCl
3
, 238C): d
3
3
.66 (d, J(H,H) 8.7 Hz, 2H), 7.33 (d, J(H,H) 8.5 Hz, 2H), 7.36 (d,
3 13
3
.85 (m, 6H), 1.25 ± 1.60 (m, 9H), 4.08 (m, 2H), 6.50 (d, J(H,H) 16.0 Hz,
3
J(H,H) 8.9 Hz, 2H), 7.41 ppm (d, J(H,H) 8.52H, 2H); C NM R
3
13
H), 7.61 (m, 3H), 8.18 ppm (d, J(H,H) 8.7 Hz, 2H);
C NM R
(
100 MHz, CDCl
3
, 238C): d 13.0, 44.8, 112.3, 120.1, 127.0, 128.1, 128.2,
(
100 MHz, CDCl
3
, 238C): d 11.4, 14.5, 23.4, 24.2, 29.4, 30.8, 39.2, 67.8,
1
32.1, 140.6, 147.8 ppm; MS (70 eV): m/z (%): 305 (62) [M] , 303 (56), 290
1
23.1, 124.6, 129.1, 141.0, 141.9, 148.9, 166.6 ppm; MS (70 eV): m/z (%): 305
(
100).
(
28) [M] , 176 (35), 70 (100).
1
1
2
6
8
8
1
1
-(4'-N,N-Diethylaminophenyl)naphthalene: H NMR (400 MHz, CDCl ,
3
1
2
'-Ethylhexyl 4-bromocinnamate: H NMR (400 MHz, CDCl
3
, 238C): d
3
3
38C): d 1.16 (t, J(H,H) 7.1 Hz, 6H), 3.36 (q, J(H,H) 7.2 Hz, 4H),
0
.84 (m, 6H), 1.24 ± 1.36 (m, 8H), 1.57 (m, 1H), 4.05 (m, 2H), 6.36 (d,
3
3
.72 (d, J(H,H) 8.5 Hz, 2H), 7.23 ± 7.44 (m, 6H), 7.71 (d, J(H,H)
3
3
3
J(H,H) 16.1 Hz, 1H), 7.34 (d, J(H,H) 8.5 Hz, 2H), 7.44 (d, J(H,H)
3
3
.1 Hz, 1H), 7.81 (d, J(H,H) 7.9 Hz, 1H), 7.99 ppm (d, J(H,H)
3
13
8
.3 Hz, 2H), 7.55 ppm (d, J(H,H) 16.1 Hz, 1H); C NMR (100 MHz,
13
.1 Hz, 1H); C NMR (100 MHz, CDCl
3
, 238C): d 13.2, 44.9, 111.8,
CDCl
3
, 238C): d 11.5, 14.5, 23.4, 24.3, 29.4, 30.9, 67.5, 119.5, 124.9, 129.9,
17.0, 126.0, 126.1, 126.2, 126.9, 127.2, 128.0, 128.7, 131.5, 132.4, 134.4, 141.1,
1
32.5, 133.8, 143.5, 167.4 ppm; MS (70 eV): m/z (%): 340 (4) [M] , 338 (4),
47.5 ppm; MS (70 eV): m/z (%): 275 (50) [M] , 260 (100).
2
28 (84), 226 (74), 70 (100).
1
3
2
6
-(4'-N,N-Diethylaminophenyl)thiophene: H NMR (400 MHz, CDCl
3
,
1
Ethyl 4-methoxycinnamate: H NMR (400 MHz, CDCl
3
, 238C): d 1.32 (t,
3
3
38C): d 1.11 (t, J(H,H) 7.1 Hz, 6H), 3.30 (q, J(H,H) 7.2 Hz, 4H),
3
3
J(H,H) 7.1 Hz, 3H), 3.83 (s, 3H), 4.24 (q, J(H,H) 7.2 Hz, 2H), 6.30 (d,
3
3
.63 (d, J(H,H) 8.7 Hz, 2H), 7.18 (s, 1H), 7.26 (d, J(H,H) 2.0 Hz, 2H),
3
3
3
J(H,H) 15.8 Hz, 1H), 6.89 (d, J(H,H) 8.7 Hz, 2H), 7.46 (d, J(H,H)
3
13
7
.38 ppm (d, J(H,H) 8.7 Hz, 2H); C NMR (100 MHz, CDCl
3
, 238C):
3
13
8
.7 Hz, 2H), 7.63 ppm (d, J(H,H) 15.9 Hz, 1H); C NMR (100 MHz,
d 13.1, 44.8, 112.3, 117.6, 126.1, 126.6, 127.9, 136.1, 143.1, 147.4 ppm; MS
CDCl
1
3
, 238C): d 14.8, 55.7, 60.7, 114.7, 116.1, 127.6, 130.1, 144.6, 161.7,
(
70 eV): m/z(%): 231 (65) [M] , 216 (100).
67.7 ppm; MS (70 eV): m/z (%): 206 (60) [M] , 161 (100).
1
3
Ethyl 4-N,N-diethylaminocinnamate: H NMR (400 MHz, CDCl , 238C):
3
3
d 1.32 (t, J(H,H) 7.1 Hz, 6H), 1.45 (t, J(H,H) 7.1 Hz, 3H), 3.55 (q,
3
3
3
J(H,H) 6.9 Hz, 4H), 4.39 (q, J(H,H) 7.1 Hz, 2H), 6.35 (d, J(H,H)
Acknowledgements
3
3
1
2
2
1
5.9 Hz, 1H), 6.79 (d, J(H,H) 8.9 Hz, 2H), 7.55 (d, J(H,H) 8.9 Hz,
H), 7.75 ppm (d, 3J(H,H) 15.9 Hz, 1H); C NMR (100 MHz, CDCl
13
,
The authors thank Dr. R. Karch (OMG) and Dr. O. Briel (OMG) for
general discussions regarding the new palladium complexes. K. S. thanks
the Alexander-von-Humboldt-Stiftung for a personal fellowship. Generous
3
38C): d 13.0, 14.9, 44.9, 60.4, 111.6, 112.2, 121.8, 130.5, 145.6, 149.7,
68.4 ppm; MS (70 eV): m/z (%): 247 (58) [M] , 232 (100).
Chem. Eur. J. 2002, 8, No. 17
¹ 2002 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
0947-6539/02/0817-3905 $ 20.00+.50/0
3905