Acetic Anhydride → N-(2-(4-(2-chlorophenyl)-4H-1,2,4-triazol-3-yl)-4,5-dihydrobenzo[b]thieno[2,3-d]oxepin-8-yl)acetamide

To a solution of 2-(4-(2-chlorophenyl)-4H-1,2,4-triazol-3-yl)-4,5-dihydro-benzo[b]thieno[2,3-d]oxepin-8-amine HCl salt (0.2 g, 0.464 mmol) in 10 ml of dried DCM was added TEA (0.32 mL, 2.3 mmol). The mixture was stirred at 0° C. for 20 min and 0.2 ml of acetic anhydride was added. After stirred for 10 min, the solution was quenched with water and evaporated to the crude product, which was purified by preparative TLC to give 115 (80 mg, 39%). 1H NMR (DMSO-d6, 400 MHz): δ 10.02 (s, 1H), 8.81 (s, 1H), 7.79-7.15 (m, 7H), 6.54 (s, 1H), 4.16 (t, J=4.8 Hz, 2H), 2.95 (t, J=4.8 Hz, 2H), 1.99 (s, 3H). MS: (ESI+) 437.1