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W.-J. Zhao et al. / Tetrahedron 61 (2005) 5585–5593
128.7, 128.5, 128.1, 128.0, 58.6, 56.0, 53.1. HRMS (EIC)
calcd for C23H20O3 (MC): 344.1412; found: 344.1416.
4.1.16. Methyl 4-oxo-4-phenyl-2-(2-thiophenyl)-butano-
ate (7e). 1H NMR (CDCl3, 400 MHz): d 7.99 (d, JZ7.6 Hz,
2H), 7.58 (t, JZ8.0 Hz, 1H), 7.49–7.45 (comp, 2H), 7.23
(s, 1H), 7.01 (s, 1H), 6.98 (s, 1H), 4.59 (dd, JZ5.2, 10.4 Hz,
1H), 3.97 (dd, JZ10.4, 18.0 Hz, 1H), 3.74 (s, 3H), 3.42
(d, JZ18.0 Hz, 1H). 13C NMR (CDCl3, 100 MHz): d 197.6,
173.4, 140.6, 136.5, 133.9, 129.1, 128.5, 127.4, 126.0,
125.2, 53.1, 43.6, 41.9. HRMS (EIC) calcd for C15H14O3S
(MC): 274.0664; found: 274.0692.
Minor isomer: 1H NMR (CDCl3, 400 MHz): d 7.86 (d, JZ
7.2 Hz, 2H), 7.53–7.22 (comp, 10H), 7.20–6.96 (comp, 3H),
5.49 (d, JZ11.6 Hz, 1H), 4.66 (d, JZ11.6 Hz, 1H), 3.39 (s,
3H). 13C NMR (CDCl3, 100 MHz): d 198.0, 172.9, 131.3,
130.7, 130.0, 129.9, 129.63, 129.6, 129.4, 129.23, 129.2,
128.5, 128.4, 128.3, 56.9, 55.9, 52.6. HRMS (EIC) calcd for
C23H20O3 (MC): 344.1412; found: 344.1416.
4.1.17. Methyl-4-oxo-4-phenyl-2-(1-tert-butyloxycarbo-
nyl-indol-3-yl)-butanoate (7f). 1H NMR (CDCl3,
400 MHz): d 8.15 (d, JZ6.8 Hz, 1H), 8.0 (d, JZ8.0 Hz,
2H), 7.70 (d, JZ7.6 Hz, 1H), 7.58–7.55 (comp, 2H), 7.47–
7.44 (comp, 2H), 7.35 (d, JZ7.2 Hz, 1H), 7.27 (d, JZ
7.2 Hz, 1H), 4.57 (dd, JZ4.0, 10.0 Hz, 1H), 4.08 (dd, JZ
10.0 Hz, 18.4 Hz, 1H), 3.71 (s, 3H), 3.37 (dd, JZ4.0,
18.4 Hz, 1H), 1.67 (s, 9H). 13C NMR (CDCl3, 100 MHz): d
198.1, 174.0, 149.9, 136.7, 133.8, 129.5, 129.1, 128.5,
125.2, 123.9, 123.2, 119.8, 118.0, 115.8, 84.4, 52.9, 41.6,
37.9, 28.6. HRMS (EIC) calcd for C24H25NO5 (MC):
407.1733; found: 407.1740.
4.1.12. Methyl 4-oxo-3-methyl-2,4-diphenylbutanoate
(3m). Major isomer: H NMR (CDCl3, 400 MHz): d 7.82
1
(d, JZ7.6 Hz, 2H), 7.50–7.23 (comp, 6H), 7.19 (t, JZ7.2,
10.8 Hz, 2H), 4.20–4.07 (comp, 2H), 3.70 (s, 3H), 1.27 (d,
JZ6.0 Hz, 3H). 13C NMR (CDCl3, 100 MHz): d 202.1,
172.9, 137.4, 136.5, 133.4, 129.0, 128.8, 128.6, 128.5,
127.7, 55.2, 52.5, 44.4, 16.4. HRMS (EIC) calcd for
C18H18O3(MC): 282.1256; found: 282.1250.
Minor isomer: 1H NMR (CDCl3, 400 MHz): d 8.06 (d, JZ
7.2 Hz, 2H), 7.60–7.23 (comp, 6H), 7.12 (t, JZ6.8, 14.0 Hz,
2H), 4.41–4.34 (comp, 2H), 3.54 (s, 3H), 0.90 (d, JZ6.0 Hz,
3H). 13C NMR (CDCl3, 100 MHz): d 204.0, 174.4, 137.3,
136.1, 133.5, 129.2, 128.9, 128.6, 128.5, 128.0, 55.2, 52.5,
44.6, 14.5. HRMS (EIC) calcd for C18H18O3 (MC):
282.1256; found: 282.1250.
4.1.18. (R)-Pantolactonyl 4-oxo-2,4-diphenylbutanoate
(8i). Major isomer: H NMR (CDCl3, 400 MHz): d 7.98
1
(d, JZ7.6 Hz, 2H), 7.60 (d, JZ7.6 Hz, 1H), 7.47–7.41
(comp, 4H), 7.37–7.34 (comp, 2H), 7.28 (d, JZ12 Hz, 1H),
5.38 (s, 1H), 4.47 (dd, JZ5.2, 9.6 Hz, 1H), 3.95 (dd, JZ9.6,
15.2 Hz, 1H), 3.92 (s, 2H), 3.41 (dd, JZ5.2, 15.2 Hz, 1H),
1.03 (s, 3H), 0.71 (s, 3H). 13C NMR (CDCl3, 100 MHz): d
197.4, 172.6, 172.5, 138.4, 136.6, 133.8, 129.4, 129.1,
128.5, 128.4, 128.3, 76.5, 75.6, 46.9, 42.6, 40.9, 23.3, 19.7.
HRMS (ESI) calcd for C22H22NaO5 (MCNaC): 389.1365;
found: 389.1346. Anal. Calcd for C22H22O5: C, 72.10; H,
6.06. Found: C, 72.03; H, 6.01.
4.1.13. Methyl 4-oxo-4-phenyl-2-(4-bromophenyl)-
butanoate (7b). H NMR (CDCl3, 400 MHz): d 7.97 (d,
1
JZ7.2 Hz, 2H), 7.58 (t, JZ7.2 Hz, 1H), 7.48–7.44 (comp,
4H), 7.26–7.23 (comp, 2H), 4.26 (dd, JZ4.0, 9.6 Hz, 1H),
3.92 (dd, JZ9.6, 18.0 Hz, 1H), 3.70 (s, 3H), 3.28 (dd, JZ
4.0, 18.0 Hz, 1H). 13C NMR (CDCl3, 100 MHz): d 197.7,
173.9, 137.7, 136.6, 133.9, 132.4, 130.0, 129.1, 128.5,
122.0, 53.0, 46.2, 42.9. HRMS (EIC) calcd for
C17H15O3Br(81) (MC): 348.0184; found: 348.0216.
HRMS (EIC) calcd for C17H15O3Br(79) (MC): 346.0205;
found: 346.0226. Anal. Calcd for C17H15O3Br: C, 58.96; H,
4.37. Found: C, 58.88; H, 4.51.
Minor isomer: 1H NMR (CDCl3, 400 MHz): d 7.98 (d, JZ
7.6 Hz, 2H), 7.58 (d, JZ6.0 Hz, 1H), 7.47–7.41 (comp, 4H),
7.37–7.34 (comp, 2H), 7.27 (d, JZ6.8 Hz, 1H), 5.35 (s, 1H),
4.38 (dd, JZ3.6, 10.8 Hz, 1H), 4.07 (dd, JZ16.0, 10.8 Hz,
1H), 3.94 (s, 2H), 3.37 (dd, JZ16.0, 3.6 Hz, 1H), 1.26 (s,
3H), 1.24 (s, 3H). 13C NMR (CDCl3, 100 MHz): d 197.8,
172.5, 172.3, 137.5, 136.6, 133.82, 128.4, 128.2, 128.1,
76.4, 75.8, 46.5, 43.4, 40.9, 23.2, 20.2. HRMS (ESI) calcd
for C22H22NaO5 (MCNaC): 389.1365; found: 389.1346.
Anal. Calcd for C22H22O5: C, 72.10; H, 6.06. Found: C,
72.03; H, 6.01.
4.1.14. Methyl 4-oxo-4-phenyl-2-(2-naphthyl)-butanoate
1
(7c). H NMR (CDCl3, 400 MHz): d 7.99 (d, JZ7.6 Hz,
2H), 7.84–7.81 (comp, 4H), 7.56 (t, JZ6.8, 4.0 Hz, 1H),
7.45–7.24 (comp, 5H), 4.47 (dd, JZ4.4, 10.0 Hz, 1H), 4.06
(dd, JZ10.0, 18.0 Hz, 1H), 3.70 (s, 3H), 3.36 (dd, JZ4.4,
18.0 Hz, 1H). 13C NMR (CDCl3, 100 MHz): d 198.0, 174.3,
136.7, 136.1, 133.87, 133.84, 133.1, 129.1, 129.0, 128.5,
128.2, 128.1, 127.1, 126.8, 126.5, 126.2, 52.9, 46.8, 43.2.
HRMS (EIC) calcd for C21H18O3 (MC): 318.1256; found:
318.1275.
4.1.19. Preparation of 4-morpholin-4-yl-2,4-diphenyl-
but-3-enoic acid methyl ester (9). To a solution of methyl
4-oxo-2,4-diphenylbutanoate (3a) (0.268 g, 1 mmol) and
morpholine (0.522 g, 6 mmol) in 10 mL anhydrous hexane,
was added TiCl4 (0.06 mL, 0.55 mmol) over 10 min. The
reaction mixture was stirred at room temperature for 24 h
and was filtered. The filtrate was evaporated under vacuum
4.1.15. Methyl 4-oxo-4-phenyl-2-(1-naphthyl)-butanoate
1
(7d). H NMR (CDCl3, 400 MHz): d 8.14 (d, JZ8.8 Hz,
1H), 7.97 (d, JZ7.6 Hz, 2H), 7.87 (d, JZ8.0 Hz, 1H), 7.79
(d, JZ7.6 Hz, 1H), 7.56–7.39 (comp, 7H), 5.19 (dd, JZ4.0,
10.0 Hz, 1H), 4.10 (dd, JZ10.0, 17.6 Hz, 1H), 3.69 (s, 3H),
3.31 (dd, JZ4.0, 17.6 Hz, 1H). 13C NMR (CDCl3,
100 MHz): d 198.2, 174.7, 136.6, 135.1, 134.5, 133.8,
131.4, 129.5, 129.0, 128.59, 128.54, 127.1, 126.3, 125.9,
125.4, 123.3, 52.9, 42.9, 42.2. HRMS (EIC) calcd for
C21H18O3 (MC): 318.1256; found: 318.1242.
1
to give a light yellow solid. H NMR (400 MHz, CDCl3):
7.36–7.19 (comp, 10H), 5.08 (d, JZ10.4 Hz, 1H), 4.18 (d,
JZ10.4 Hz, 1H), 3.82 (m, 2H), 3.68 (m, 2H), 3.63 (s, 3H),
3.04 (m, 2H), 2.78 (m, 2H). IR (KBr): 2962 (s), 2910 (s),
2717 (m), 2443 (w), 1731 (s), 1615 (s), 1599 (s), 1495
(s) cmK1. HRMS (ESI) calcd for C21H24O3N (MCHC):
338.1756; found: 338.1739.