Isopropanol → Etamicastat

Participants

Reaction Conditions

Reaction Steps

(R)-5-(2-Aminoethyl)-1-(6,8-difluorochroman-3-yl)-1,3-dihydroimidazole-2-thione hydrochloride (9.64 g, 27.72 mmol) was dissolved in water (160 ml) at 40-45° C. with stirring. To the resulting solution 2-propanol (64 ml) was added, the mixture was cooled to 35-38° C., dichloromethane (256 ml) was added followed by 1N NaOH (28 ml, 28 mmol) and the stirring continued for 10-15 min. Lower organic phase was separated, dried over MgSO4 and evaporated under reduced pressure to approx. 40 ml. The resulting suspension was diluted with petroleum ether (200 ml), the precipitate was collected, was with petroleum ether on the filter, dried in vacuum. Yield 7.8 g (91%), mp 192-5° C. (dec).

Provenance & Evidence