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arom H), 7.18-7.16 (2H, m, arom H), 3.36-3.33 (1H, m, CH), 3.31 (3H, s, N-Me), 2.02 (3H, s, Ac),
1.94-1.71 (1H, m, H-CH), 1.70-1.64 (1H, m, HC-H), 1.30-1.24 (1H, m, H-CH), 1.20-1.13 (1H, m, HC-H),
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0.82 (3H, t, J = 7.5 Hz, Me) ppm. C NMR (125 MHz, CDCl3): ! 205.0 (C=O), 169.5 (N-C=O), 143.4,
130.0, 128.3, 127.7 (arom C), 57.6 (CH), 37.7 (N-Me), 31.7, 21.0 (CH2), 28.1 (Ac), 13.9 (Me) ppm.
2-Isopropyl-N-methyl-3-oxo-N-phenylbutanamide (6p). Yield 43%. Brown liquid. IR (CHCl3): " 1717
(C=O), 1651 (CONH) cm-1. 1H NMR (500 MHz, CDCl3): ! 7.46-7.43 (2H, m, arom H), 7.39-7.36 (1H, m
arom H), 7.13-7.11 (2H, m, arom H), 3.30 (3H, s, N-Me), 3.05 (1H, d, J = 10.5 Hz, CH), 2.50 (1H, m,
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CH), 2.17 (3H, s, Ac), 0.92 (3H, d, J = 7.0 Hz, Me), 0.75 (3H, d, J = 7.0 Hz, Me) ppm. C NMR (125
MHz, CDCl3): ! 205.0 (C=O), 168.7 (N-C=O), 143.3, 129.9, 128.2, 127.9 (arom C), 66.1 (CH), 37.8
(N-Me), 30.3 (Ac), 27.6 (CH), 21.0, 20.1 (Me) ppm. FAB HRMS (acetone/NBA) calcd for C14H20NO2
234.1494 (M+H). Found 234.1499.
2-Butyl-N-methyl-3-oxo-N-phenylbutanamide (6q).19 Yield 33%. Orange liquid. IR (CHCl3): " 1720
(C=O), 1651 (CONH) cm-1. 1H NMR (500 MHz, CDCl3): ! 7.46-7.43 (2H, m, arom H), 7.39-7.36 (1H, m
arom H), 7.18-7.16 (2H, m, arom H), 3.34-3.30 (1H, m, CH), 3.31 (3H, s, N-Me), 2.06 (3H, s, Ac),
1.93-1.87 (1H, m, H-CH), 1.73-1.68 (1H, m, HC-H), 1.26-1.18 (2H, m, CH2), 1.14-1.08 (2H, m, CH2),
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0.85 (3H, t, J = 7.0 Hz, Me) ppm. C NMR (125 MHz, CDCl3): ! 205.0 (C=O), 169.5 (N-C=O), 143.4,
130.0, 128.3, 127.8 (arom C), 57.8 (CH), 37.7 (N-Me), 28.0 (Ac), 29.8, 29.3, 22.4 (CH2), 13.7 (Me) ppm.
N,2-Dimethyl-N-(1-naphthyl)-3-oxobutanamide (6r). Rotamer ratio = 1.2:1. Yield 77%. Colorless
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microcystals (from EtOH), mp 79 °C. IR (CHCl3): " 1719 (C=O), 1651 (CONH) cm-1. H NMR (300
MHz, CDCl3): ! 7.92-7.31 (7H, m, arom H), 3.42 (3H, s, NMe), 3.18-3.13 (1H, m, CH), 1.97, 1.95 (3H, s,
Ac), 1.26, 1.19 (3H, d, J = 6.9 Hz, Me) ppm. 13C NMR (75 MHz, CDCl3): ! 205.1, 203.8 (C=O), 171.9,
171.0 (N-C=O), 139.4, 139.2, 134.7, 134.6, 129.9, 129.8, 129.2, 129.0, 128.8, 128.7, 127.7, 127.6, 127.0,
126.9, 126.0, 125.8, 125.7, 125.5, 122.2, 121.8 (arom C), 51.7, 51.4 (CH), 37.2 (N-Me), 28.0, 27.8 (Ac),
14.2, 14.1 (Me) ppm. MS (rel intensity): m/z 255 (45), 157 (100), 128 (40), 112 (80), 70 (45). Anal. Calcd
for C16H17NO2: C, 75.27; H, 6.71; N, 5.49. Found: C, 75.28; H, 6.92; N, 5.52.
N,2-Dimethyl-N-(2-naphthyl)-3-oxobutanamide (6s). Yield 79%. Colorless microcystals (from EtOH),
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mp 103 °C. IR (CHCl3): " 1726 (C=O), 1654 (CONH) cm-1. H NMR (300 MHz, CDCl3): ! 7.96-7.85
(3H, m, arom H), 7.71 (1H, m, aron H), 7.56-7.53 (2H, m, arom H), 7.35-7.31 (1H, m, arom H), 3.49 (1H,
q, J = 6.9 Hz, CH), 3.39 (3H, s, NMe), 2.00 (3H, s, Ac), 1.28 (3H, d, J = 6.9 Hz, Me) ppm. 13C NMR (75
MHz, CDCl3): ! 204.1 (C=O), 170.3 (N-C=O), 140.3, 133.1, 132.0, 129.9, 127.4, 127.3, 126.7, 126.6,
125.6, 124.6 (arom C), 51.3 (CH), 37.1 (N-Me), 27.6 (Ac), 13.3 (Me) ppm. MS m/z (rel intensity): 255
(55, M+), 157 (100), 127 (35), 112 (30). Anal. Calcd for C16H17NO2: C, 75.27; H, 6.71; N, 5.49. Found: C,
75.11; H, 6.91; N, 5.47.