Reaction Steps
Reaction of N-tert-butoxycarbonyl-L-methionine (1a) and 2-chloroaniline (2b) according to General Procedure A, gave after purification on a SILICA GEL column with hexane-acetone (3:1) as the eluent, an oily liquid of (3b) (C16H23N2O3S1Cl1, 79%), Rf=0.43 (hexane-acetone 3:1), [α]D23 =-41.5° (c 0.65, CHCl3), IR (KBr) ν: 536, 548, 606, 648, 667, 691, 752, 864, 963, 1036, 1055, 1165, 1250, 1298, 1368, 1393, 1441, 1524, 1593, 1616, 1684, 1696, 2338, 2361, 2870, 2920, 2978, 3036, 3061, 3121, 3314 cm-1, 1H NMR (CDCl3) δ: 8.551 (s, 1H, Ar--NH), 8.321-8.355 (m, 1H, ArH), 7.334-7.336 (m, 1H, ArH), 7.221-7.279 (m, 1H, ArH), 7.005-7.062 (m, 1H, ArH), 5.194-5.214 (br s, 1H, NH), 4.442-4.462 (m, 1H, Hα), 2.590-2.638 (m, 2H, CH2γ), 2.144-2.281 (m, 1H, Hβ), 2.112 (s, 3H, CH3ε), 1.966-2.112 (m, 1H, Hβ), 1.44 (s, 9H, t-Bu); EIMS (70 eV) m/z (%): 358 (M+, 2).
