Reaction Steps
Coupling of N-tert-butoxycarbonyl-L-methionine (1a) and 3-chloroaniline (2c) according to General Procedure A, gave after purification on a SILICA GEL column hexane-acetone (3:1) an oily liquid of (3c) (C16H23N2O3S1Cl1, 94%), Rf=0.40 (hexane-acetone 3:1), [α]D23 =-36.8° (c 1.44, CHCl3), IR (KBr) ν: 440, 461, 519, 548, 606, 681, 739, 777, 864, 880, 903, 963, 999, 1026, 1049, 1076, 1099, 1165, 1252, 1267, 1300, 1368, 1393, 1427, 1456, 1483, 1506, 1522, 1539, 1595, 1670, 1684, 1697, 2336, 2361, 2868, 2918, 2978, 3061, 3086, 3131, 3198, 3291, 3522, 3545 cm-1, 1H NMR (CDCl3) δ: 8.472 (br s, 1H, Ar--NH), 7.616-7.629 (m, 1H, ArH), 7.240-7.283 (m, 1H, ArH), 7.153 (dd, 1H, J 7.8 Hz and 8.1 Hz, ArH), 7.023 (d, 1H, J 7.8 Hz, ArH), 5.377 (br s, 1H, NH), 4.407-4.427 (m, 1H, Hα), 2.566-2.618 (m, 2H, CH2γ), 2.116-2.184 (m, 1H, Hβ), 2.084 (s, 3H, CH3ε), 1.940-2.070 (m, 1H, Hβ), 1.425 (s, 9H, t-Bu); EIMS (70 eV) m/z (%): 358 (M+, 2).
