Reaction Steps
To a solution of 34 (0.106 g, 0.271 mmol) in DCM (2 ml) TFA (2 ml) was added. After stirring for 2 h at room temperature, the solvent was distilled under reduced pressure to give a brown solid. The crude residue was dissolved as obtained in 1,4-dioxane:H2O 1:1 (5 ml) and K2CO3 (0.225 g, 1.63 mmol, 6 eq) was added followed by tosyl chloride (0.056 g, 0.298 mmol, 1.1 eq) at room temperature. After stirring for 2 h at room temperature, the resulting mixture was evaporated in vacuo to dryness. Water (10 ml) was added and the resulting white solid was separated by filtration and dried. Pure 36 was obtained without further purification (0.079 g, 0.179 mmol, 66%), mp 200-202° C. 1H NMR (400 MHz, CD3OD) δ 2.39 (3H, s, Ar—CH3), 2.56 (1H, dd, J 9.2, 14.4 Hz, H—CHCO), 2.77 (1H, dd, J 6.8, 14.4 Hz, H—CHCO), 3.06 (1H, dd, J 8.2, 13.0 Hz, H—CHNH), 3.15 (1H, dd, J 6.8, 13.2 Hz, H—CHNH) 7.03-7.07 (1H, m, CH, Ar), 7.15 (2H, d, J 8.4 Hz, 2×CH, Ar), 7.21-7.26 (4H, s, 4×CH, Ar), 7.29 (2H, d, J 8.0 Hz, 2×CH, Ar), 7.36-7.38 (2H, m, 2×CH, Ar), 7.62 (2H, d, J 8.8 Hz, 2×CH, Ar). 13C NMR (400 MHz, DMSO-d6) δ21.63 (s) (Ar—CH3), 40.73 (s) (CH2CO), 41.87 (s) (CH2CHCH2), 48.13 (s) (CH2NH), 119.79 (s) (2×CH, Ar), 123.80 (s) (CH, Ar), 127.14 (s) (2×CH, Ar), 128.80 (s) (2×CH, Ar), 129.29 (s) (2×CH, Ar), 130.23 (s) (2×CH, Ar), 130.36 (s) (2×CH, Ar), 131.80 (s) (C, Ar), 138.14 (s) (C, Ar), 139.64 (s) (C, Ar), 141.53 (s) (C, Ar), 143.20 (s) (C, Ar), 169.81 (s) (C═O). νmax (pure sample)/(cm−1) 3340 (md) (N—H), 3141 (md) (N—H), 1665 (st) (C═O), 1598 (st), 1547 (st), 1493 (md), 1444 (st), 1154 (st), 1087 (md). MS (API-ES): m/z 443 [M+H]+ (100%), HRMS (API-ES) m/z found 443.1201 [M+H]+.
