Water → 2-[3(2-propynyl)-6-fluoro-2(3H)-benzothiazolon-5-yl]-4, 5, 6,7-tetrahydro-2H-benzotriazole-1-oxide

Participants

Reaction Steps

To a dispersion of sodium hydride (60% oil; 31 mg) in dry N,N-dimethylformamide (3 ml) was added 2-[6-fluoro-2(3H)-benzothiazolon-5-yl]-4,5,6,7-tetrahydro-2H-benzotriazole-1-oxide (220 mg) at 0° C., and the resultant mixture was stirred at the same temperature for 30 minutes, followed by addition of propargyl bromide (94 mg). The mixture was allowed to react at 50° to 60° C. for 3 hours. Water was added to the reaction mixture, which was then extracted with ethyl acetate. The extract was washed with water, dried and concentrated. The residue was purified by silica gel thin layer chromatography using a mixture of ethyl acetate and toluene (1:9) as an eluent to give 2-[3-(2-propynyl)-6-fluoro-2(3H)-benzothiazolon-5-yl]-4,5,6,7-tetrahydro-2H-benzotriazole-1-oxide (Compound No. 5; 120 mg). nD25.4 1.5988.

Provenance & Evidence