Chloroform → HCID 12223711, compound

Reaction equation

[F:1][C:2]([F:21])([F:20])[C:3]1[CH:16]=[C:15]2[C:6]([S:7][C:8]3[CH:9]=[CH:10][CH:11]=[C:12]([C:17](O)=[O:18])[C:13]=3[NH:14]2)=[CH:5][CH:4]=1.C(Cl)(Cl)[Cl:23].P(Cl)(Cl)Cl>CN(C)C=O>[F:1][C:2]([F:21])([F:20])[C:3]1[CH:16]=[C:15]2[C:6]([S:7][C:8]3[CH:9]=[CH:10][CH:11]=[C:12]([C:17]([Cl:23])=[O:18])[C:13]=3[NH:14]2)=[CH:5][CH:4]=1

Participants

Procedure

8-Trifluoromethylphenothiazine-1-carboxylic acid (62.2 g., 0.20 mol.) was added to a stirred mixture of 300 ml. of chloroform and 300 ml. of phosphorus trichloride. The resulting brown suspension was cooled in an ice-bath while 50 ml. of dimethylformamide was added slowly until a reddish brown solution formed. After stirring the mixture for 4 hours at 25°, the chloroform and excess phosphorus trichloride were evaporated under reduced pressure. The resulting reddish brown solid residue was dissolved in 1500 ml. of boiling n-hexane. The hot, clear, reddish solution was decanted from a viscous, insoluble material and, on cooling, large red needles formed. The solid was collected by filtration and washed with hexane to give 8-trifluoromethylphenothiazine-1-carboxylic acid chloride, m.p. 124°-126°.