G. Chen et al. / Tetrahedron 67 (2011) 2332e2337
2335
(300 MHz, CDCl3):
d
7.41e7.26 (m, 4H), 7.25e7.16 (m,1H), 6.15e6.06
1452,1402,1379,1361,1273,1195,1153,1105,1076,1014; HRMS calcd
for C24H25NO (Mþ): 343.1936. Found: 343.1938.
(m, 1H), 5.89 (s, 1H), 4.53 (s, 2H), 2.20e1.95 (m, 4H), 1.49 (s, 6H),
1.04 (t, J¼7.5 Hz, 6H); 13C NMR (75 MHz, CDCl3):
d 205.0, 162.9,
158.6, 141.3, 128.2, 127.9, 126.2, 117.7, 110.9, 89.3, 88.2, 51.2, 26.3,
25.3, 11.9; MS (m/z): 296 (Mþþ1, 21.64), 295 (Mþ, 100); IR (neat,
cmꢁ1): 2970, 2933, 2871, 1941, 1678, 1606, 1495, 1453, 1379, 1361,
1325, 1270, 1193, 1161, 1111, 1031; HRMS calcd for C20H25NO (Mþ):
295.1936. Found: 295.1947.
4.2.7. (Z)-N-(n-Butyl)5,5-dimethyl-4-(20-methylocta-20,30-dien-40-yl)
furan-2(5H)-imine (3be). The reaction of 33.2 mg (0.20 mmol) of
1a, 80.0 mg (0.41 mmol) of 2e, 2.3 mg (0.010 mmol) of Pd(OAc)2,
4.8 mg (0.021 mmol) of TFP, and 27.8 mg (0.20 mmol) of K2CO3 in
2 mL of DMSO afforded 30.2 mg (53%, 73% by NMR) of 3be (eluent:
petroleum ether/ethyl acetate¼7/1 to 5/1) as a liquid. 1H NMR
4.2.3. (Z)-N-Benzyl 4-(30,30-pentamethylenepropa-10,20-dienyl)-5,5-
dimethylfuran-2(5H)-imine (3ac). The reaction of 40.7 mg (0.20
mmol) of 1a, 73.0 mg (0.40 mmol) of 2c, 2.2 mg (0.010 mmol) of
Pd(OAc)2, 4.7 mg (0.020 mmol) of TFP, and 28.1 mg (0.20 mmol)
of K2CO3 in 2 mL of DMSO afforded 34.9 mg (56%, 74% by NMR) of
3ac (eluent: petroleum ether/ethyl acetate¼7/1 to 5/1 to 3/1) as
(300 MHz, CDCl3):
J¼7.2 Hz, 2H), 1.74 (s, 6H), 1.61e1.47 (m, 2H), 1.46e1.25 (m, 6H), 1.41
(s, 6H), 0.95e0.82 (m, 6H); 13C NMR (75 MHz, CDCl3):
204.4,162.4,
d
5.81 (s, 1H), 3.28 (t, J¼7.1 Hz, 2H), 2.13 (t,
d
160.1, 116.3, 97.9, 96.9, 89.6, 46.6, 33.3, 30.5, 29.7, 26.3, 22.2, 20.6,
20.0, 14.0, 13.9; MS (m/z): 290 (Mþþ1, 12.96), 289 (Mþ, 55.29), 246
(100); IR (neat, cmꢁ1): 2957, 2930, 2861, 1948, 1679, 1599, 1460,
1377, 1361, 1279, 1194, 1126; HRMS calcd for C19H31NO (Mþ):
289.2406. Found: 289.2414.
a liquid. 1H NMR (300 MHz, CDCl3):
d 7.42e7.25 (m, 4H), 7.24e7.15
(m, 1H), 5.97e5.89 (m, 1H), 5.87 (s, 1H), 4.53 (s, 2H), 2.30e2.12 (m,
4H), 1.77e1.53 (m, 6H), 1.50 (s, 6H); 13C NMR (75 MHz, CDCl3):
d
203.2, 162.9, 158.5, 141.3, 128.2, 127.9, 126.2, 117.7, 104.9, 89.3,
4.2.8. (Z)-N-(tert-Butyl)5,5-dimethyl-4-(20-methylocta-20,30-dien-40-
yl)furan-2(5H)-imine (3ce). The reaction of 33.8 mg (0.20 mmol) of
1c, 80.2 mg (0.41 mmol) of 2e, 2.3 mg (0.010 mmol) of Pd(OAc)2,
4.6 mg (0.020 mmol) of TFP, and 27.6 mg (0.20 mmol) of K2CO3 in
2 mL of DMSO afforded 39.6 mg (68%, 79% by NMR) of 3ce (eluent:
petroleum ether/ethyl acetate¼4/1 to 3/1 to 1/1) as a liquid. 1H
84.6, 51.2, 30.7, 26.6, 26.1, 25.7; MS (m/z): 308 (Mþþ1, 18.55), 307
(Mþ, 80.56), 91 (100); IR (neat, cmꢁ1): 2985, 2929, 2855, 1948,
1681, 1609, 1584, 1549, 1495, 1447, 1374, 1361, 1259, 1236, 1191,
1155, 1111, 1074, 1026; HRMS calcd for C21H25NO (Mþ): 307.1936.
Found: 307.1935.
NMR (300 MHz, CDCl3):
d
5.81 (s, 1H), 2.12 (t, J¼7.2 Hz, 2H), 1.74 (s,
4.2.4. (Z)-N-Benzyl
5,5-dimethyl-4-(30-phenylbuta-10,20-dienyl)fu-
6H), 1.45e1.23 (m, 4H), 1.41 (s, 6H), 1.29 (s, 9H), 0.87 (t, J¼7.2 Hz,
ran-2(5H)-imine (3ad). The reaction of 40.1 mg (0.20 mmol) of 1a,
83.1 mg (0.41 mmol) of 2d, 2.3 mg (0.010 mmol) of Pd(OAc)2,
4.6 mg (0.020 mmol) of TFP, and 27.7 mg (0.20 mmol) of K2CO3 in
2 mL of DMSO afforded 37.4 mg (57%, 61% by NMR) of 3ad (eluent:
petroleum ether/ethyl acetate¼7/1 to 5/1 to 3/1) as a liquid. 1H
3H); 13C NMR (75 MHz, CDCl3):
d 204.4, 160.7, 159.2, 117.9, 97.8,
96.8, 90.2, 53.0, 30.6, 29.8, 26.2, 22.3, 20.1, 13.9; MS (m/z): 289 (Mþ,
3.05), 274 (100); IR (neat, cmꢁ1): 2963, 2930, 2862,1948,1681,1601,
1458, 1385, 1360, 1273, 1218, 1195, 1123; HRMS calcd for C19H31NO
(Mþ): 289.2406. Found: 289.2409.
NMR (300 MHz, CDCl3):
d
7.45e7.18 (m, 10H), 6.43 (q, J¼3.0 Hz, 1H),
6.04 (s, 1H), 4.55 (s, 2H), 2.22 (d, J¼3.0 Hz, 3H), 1.51 (s, 3H), 1.40 (s,
4.2.9. (Z)-N-(tert-Butyl)5,5-dimethyl-4-(30-methyl-10-phenylbuta-
10,20-dienyl)furan-2(5H)-imine (3cf). The reaction of 34.0 mg (0.20
mmol) of 1c, 89.2 mg (0.41 mmol) of 2f, 2.2 mg (0.010 mmol) of Pd
(OAc)2, 4.7 mg (0.020 mmol) of TFP, and 27.7 mg (0.20 mmol) of
K2CO3 in 2 mL of DMSO afforded 58.5 mg (93%, 95% by NMR) of 3cf
(eluent: petroleum ether/ethyl acetate¼5/1 to 1/1.5) as a solid, mp:
91.5e92.8 ꢀC (n-hexane/CH2Cl2). 1H NMR (300 MHz, CDCl3):
3H); 13C NMR (75 MHz, CDCl3):
d
209.6, 162.8, 157.3, 141.0, 134.4,
128.6, 128.2, 127.9, 127.6, 126.3, 125.8, 119.2, 103.8, 89.4, 88.7, 51.2,
26.1, 26.0, 16.5; MS (m/z): 330 (Mþþ1, 16.64), 329 (Mþ, 65.43), 91
(100); IR (neat, cmꢁ1): 3087, 3061, 3028, 2980, 2930, 2865, 1930,
1674, 1605, 1494, 1453, 1362, 1347, 1280, 1184, 1160, 1110, 1066,
1027; HRMS calcd for C23H23NO (Mþ): 329.1780. Found: 329.1790.
d
7.30e7.12 (m, 5H), 5.69 (s,1H),1.76 (s, 6H),1.46 (s, 6H),1.23 (s, 9H);
4.2.5. (Z)-N-Benzyl 5,5-dimethyl-4-(20-methylocta-20,30-dien-40-yl)
furan-2(5H)-imine (3ae). The reaction of 39.5 mg (0.20 mmol) of
1a, 80.5 mg (0.41 mmol) of 2e, 2.2 mg (0.010 mmol) of Pd(OAc)2,
4.7 mg (0.020 mmol) of TFP, and 27.8 mg (0.20 mmol) of K2CO3 in
2 mL of DMSO afforded 44.6 mg (70%, 77% by NMR) of 3ae (eluent:
petroleum ether/ethyl acetate¼7/1) as a liquid. 1H NMR (300 MHz,
13C NMR (75 MHz, CDCl3):
d
205.5, 160.1, 157.8, 136.7, 128.7, 128.2,
127.4, 121.3, 100.5, 98.4, 90.2, 53.0, 29.7, 26.1, 20.1; MS (m/z): 309
(Mþ, 1.39), 294 (100); IR (neat, cmꢁ1): 2967, 1940, 1682, 1594, 1492,
1446, 1380, 1360, 1271, 1218, 1191, 1149, 1098, 1020. Anal. Calcd for
C21H27NO: C 81.51, H 8.79, N 4.53. Found: C 81.46, H 8.62, N 4.47.
CDCl3):
d
7.42e7.26 (m, 4H), 7.25e7.15 (m, 1H), 5.90 (s, 1H), 4.53 (s,
4.2.10. (Z)-N-Benzyl 5-ethyl-5-methyl-4-(20-methylocta-20,30-dien-
40-yl)furan-2(5H)-imine (3de). The reaction of 43.0 mg (0.20 mmol)
of 1d, 80.2 mg (0.41 mmol) of 2e, 2.2 mg (0.010 mmol) of Pd(OAc)2,
4.7 mg (0.020 mmol) of TFP, and 27.7 mg (0.20 mmol) of K2CO3 in
2 mL of DMSO afforded 34.2 mg (51%, 59% by NMR) of 3de (eluent:
petroleum ether/ethyl acetate¼8/1) as a liquid. 1H NMR (300 MHz,
2H), 2.17 (t, J¼7.2 Hz, 2H), 1.77 (s, 6H), 1.47 (s, 6H), 1.45e1.27 (m,
4H), 0.90 (t, J¼6.9 Hz, 3H); 13C NMR (75 MHz, CDCl3):
d 204.5, 163.0,
160.6, 141.3, 128.2, 127.8, 126.2, 116.2, 98.0, 96.9, 90.0, 51.1, 30.5,
29.7, 26.3, 22.2, 20.0, 13.9; MS (m/z): 324 (Mþþ1, 20.81), 323 (Mþ,
85.37), 175 (100); IR (neat, cmꢁ1): 2961, 2930, 2860, 1947, 1678,
1598, 1495, 1452, 1379, 1361, 1282, 1194, 1125, 1028; HRMS calcd for
C22H29NO (Mþ): 323.2249. Found: 323.2245.
CDCl3): d 7.42e7.27 (m, 4H), 7.24e7.16 (m, 1H), 5.96 (s, 1H), 4.53 (d,
J¼1.2 Hz, 2H), 2.17 (t, J¼7.2 Hz, 2H), 1.84e1.70 (m, 8H), 1.48e1.24
(m, 1H), 1.44 (s, 6H), 0.90 (t, J¼7.2 Hz, 3H), 0.70 (t, J¼7.4 Hz, 3H); 13C
4.2.6. (Z)-N-Benzyl 5,5-dimethyl-4-(30-methyl-10-phenylbuta-10,20-
dienyl)furan-2(5H)-imine (3af). Thereactionof40.6 mg(0.20 mmol)
of 1a, 86.3 mg (0.40 mmol) of 2f, 2.3 mg (0.010 mmol) of Pd(OAc)2,
4.7 mg (0.020 mmol) of TFP, and 27.8 mg (0.20 mmol) of K2CO3 in
2 mL of DMSO afforded 49.8 mg (72%, 88% by NMR) of 3ae (eluent:
petroleum ether/ethyl acetate¼5/1) as a liquid. 1H NMR (300 MHz,
NMR (75 MHz, CDCl3): d 204.2, 163.6, 158.6, 141.3, 128.2, 127.9,
126.2, 117.7, 97.9, 97.0, 92.7, 51.1, 31.2, 30.6, 29.8, 25.7, 22.3, 20.1,
20.0, 13.9, 7.5; MS (m/z): 338 (Mþþ1, 26.93), 337 (Mþ, 100); IR (neat,
cmꢁ1): 2967, 2931, 2872, 1947, 1677, 1598, 1495, 1452, 1377, 1350,
1305, 1248, 1129, 1028; HRMS calcd for C23H31NO (Mþ): 337.2406.
Found: 337.2426.
CDCl3):
d
7.42e7.17 (m,10H), 5.85 (s,1H), 4.54 (s, 2H),1.86 (s, 6H),1.59
205.7, 162.6, 159.3, 141.2, 136.7,
(s, 6H); 13C NMR (75 MHz, CDCl3):
d
4.2.11. (Z)-N-Benzyl 3,5,5-trimethyl-4-(30-methylbuta-10,20-dienyl)
furan-2(5H)-imine (3ea). The reaction of 43.5 mg (0.20 mmol) of
1e, 58.1 mg (0.41 mmol) of 2a, 2.2 mg (0.010 mmol) of Pd(OAc)2,
4.6 mg (0.020 mmol) of TFP, and 27.6 mg (0.20 mmol) of K2CO3 in
128.7,128.3,128.2,127.8,127.5,126.2,119.5,100.6,98.6, 90.1, 51.2, 26.3,
20.1;MS(m/z):344 (Mþþ1,12.65), 343 (Mþ, 46.82), 91 (100); IR(neat,
cmꢁ1): 3060, 3027, 2978, 2930, 2856, 1943, 1676, 1598, 1548, 1494,