2-Benzothiazolinone, hydrazone → 1-(2-Benzothiazolyl)-5-(4-chlorophenyl)-5-hydroxy-3-(3-hydroxypropyl)-2-pyrazoline

Participants

Reaction Steps

6-(4-Chlorophenyl)-4,6-diketohexanol (7.2 g, 30 mM) was treated with 2-hydrazinobenzothiazole (4.96 g, 30 mM) in pyridine (5 ml) and MeOH (150 ml) at reflux for 2 hr and then allowed to stand at RT for 48 hr. The solvents were removed in vacuo and the crude residue purified by flash chromatography on silica with Et2O:Et3N (2.5%) as eluent. The title compound (1) was obtained as a pale yellow solid, (3.15 g, mp=132°-134° C.) upon recrystallization from Et2O:hexane. NMR(CDCl3) δ 3.2 (2H, C4 -H); MS, m/e 387 (M+).

Provenance & Evidence