Imidazole → N-(4-cyano-2-t-butyldimethylsilanoxyphenyl)-N'-(2-bromophenyl)thio urea

Participants

Reaction Steps

To a solution of N-(4-cyano-2-hydroxyphenyl)-N′-(2-bromophenyl)thio urea (3.5 g, 10 mmol) in THF (50 mL) at 0° C. was added imidazole (1.0 g, 15 mmol) and TBSCl (1.5 g, 10 mmol). After 1 h, the reaction mixture quenched with water (100 mL) and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The crude material was crystallized from ethyl acetate to give 3.9 g (84%) of N-(4-cyano-2-t-butyldimethylsilanoxyphenyl)-N′-(2-bromophenyl)thio urea as a yellow solid. 1H NMR (400 MHz, DMSO) δ 9.9 (s, 1H), 9.2 (s, 1H), 8.1 (d, 1H), 7.7 (d, 1H), 7.6 (d, 1H), 7.45 (d, 1H), 7.4 (t, 1H), 7.35 (s, 1H), 7.2 (t, 1H); MS(EI) m/e 347 (100 (M+)), 175 (40), 461 (40).

Provenance & Evidence