Fumaric Acid → N-propyl-10-[1-(1-pyrrolidinyl)-2-propyl]-2-phenothiazinecarboxamide

Participants

Reaction Conditions

Reaction Steps

Fumaric acid (2.7 g) is added to a solution of N-propyl-10-[1-(1-pyrrolidinyl)-2-propyl]-2-phenothiazinecarbothioamide, L series (9.5 g) in ethanol (100 cc). The solution obtained is concentrated to dryness under reduced pressure (30 mm Hg; 4 kPa) at 40° C. The merigue-like yellow residue is taken up with acetic acid (200 cc). Mercuric acetate (7.3 g) is added to the solution obtained, and the mixture is stirred for 16 hours at a temperature in the region of 20° C. The black suspension obtained is diluted with distilled water (200 cc) and filtered. The yellow filtrate is concentrated under reduced pressure (30 mm Hg; 4 kPa) at 40° C. The residue is taken up with ethyl acetate (250 cc) and distilled water (50 cc) and then treated with sodium hydroxide (d 1.33) to pH 13. The aqueous phase is separated after settling has taken place and extracted with ethyl acetate (250 cc). The organic phases are combined, washed successively with distilled water (2×100 cc) and with saturated aqueous sodium chloride solution (100 cc) and dried over magnesium sulphate. After filtration, the yellow filtrate is concentrated under reduced pressure (30 mm Hg; 4 kPa) at 40° C. and a crude yellow oil (9.2 g) is thereby obtained. This residue is purified by chromatography on a column (height: 22 cm; diameter: 4 cm) of silica gel (0.2-0.063 mm), eluting with a mixture (95:5 by volume) of methylene chloride and methanol. The first 1,500 cc are discarded and the next 1,500 cc are concentrated under reduced pressure (30 mm Hg; 4 kPa) at 40° C. to give N-propyl-10-[1-(1-pyrrolidinyl)-2-propyl]-2-phenothiazinecarboxamide, L series (7.3 g) in the form of a yellow gum.

Provenance & Evidence