Hydrogen Sulfide → 10-[(1RS)-2-hydroxy-1-methylethyl]-2-phenothiazinecarbothioamide

Participants

Reaction Steps

Triethylamine (98.4 cc) is added to a solution of 10-[(1RS)-2-hydroxy-1-methylethyl]-2-phenothiazine-carbonitrile (197.7 g) in anhydrous pyridine (750 cc), and hydrogen sulphide is bubbled through for 6 hours 30 minutes at 25° C. while the mixture is kept stirred. The mixture is stirred for 16 hours at 25° C., then purged with a stream of nitrogen for 2 hours and poured into distilled water (3000 cc). The oil which forms is separated after settling has taken place, washed with distilled water (3×1000 cc) and dissolved in ethyl acetate (3000 cc). The solution obtained is washed with distilled water (7×1 liter), dried over magnesium sulphate, filtered and concentrated to dryness under reduced pressure (30 mm Hg; 4 kPa) at 40° C. to give a yellow crystalline mass (225 g). This product is recrystallized in ethanol (1350 cc) to give 10-[(1RS)-2-hydroxy-1 -methylethyl]-2-phenothiazinecarbothioamide (158.4 g) in the form of yellow crystals, m.p. 152° C.

Provenance & Evidence