Chloroacetyl chloride → 2-Chloro-1-(7-nitro-2H-benzo[b][1,4]thiazin-4(3H)-yl)ethanone

Participants

Reaction Conditions

Reaction Steps

2-Chloroacetyl chloride (4.08 mL, 50.9 mmol) was added dropwise to a solution containing 7-nitro-3,4-dihydro-2H-benzo[b][1,4]thiazine (5 g, 25.5 mmol) in toluene (30 mL). The mixture was refluxed at 110° C. for 20 minutes. The mixture was quenched with saturated sodium bicarbonate solution (100 mL). The mixture was transferred to a separatory funnel and extracted with EtOAc (4×100 mL). The crude material was filtered through a pad of silica gel and washed with EtOAc. The filtrate was concentrated to give a yellow-brown solid. 1H-NMR (DMSO-d6) δ 8.12 (d, J=2.7 Hz, 1H), 7.94 (dd, J=2.7, 9.0 Hz, 1H), 7.72 (d, J=9.0 Hz, 1H), 4.63 (s, 2H), 3.96 (t, J=5.1 Hz, 2H), 3.32 (t, J=5.4 Hz, 2H, overlap with solvent peak); ESI-MS (m/z, %): 273 (MH+, 100), 295 (40).

Provenance & Evidence