反应详情

A mixture of 2-butyl-1,2,4-thiadiazolo[4,5-a]benzimidazole-3(2H)-one (10.0 g, 40.4 mmole) and p-toluenesulfonyl cyanide (14.7 g, 81.0 mmole) in 120 mL of dichloromethane was stirred at room temperature for 20 h. The precipitate was filtered and washed with dichloromethane to yield 12.2 g (91%) of 3-(4-methylphenylsulfonyl)-1,2,4-thiadiazolo[4,5-a]benzimidazole as white powder: mp 231°-234° C.; 1H NMR (CDCl3) δ8.53 (d, 1H), 8.04 (d, 2H), 7.82 (d, 1H), 7.56-7.44 (m, 4H), 2.53 (s, 3H) ppm; 13C NMR (CDCl3) δ163.72, 150.38, 147.97, 147.54, 132.48, 130.30(2C), 129.97(2C), 128.49, 126.14, 123.06, 119.70, 114.67, 21.93 ppm; IR (KBr) ν1592, 1525, 1444, 1337, 1151, 1081, 735 cm-1 ; HRMS calcd for C15H11N3O2S2 : 329.0293, found: 329.0300. Anal. Calcd for C15H11N3 O2S2 : C, 54.70; H, 3.37; N, 12.76. Found: C, 54.29; H, 3.14; N, 14.59.

1. filtrationThe precipitate was filtered
2. washwashed with dichloromethane