Acetic Anhydride → Fthalide

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-(4-(dimethylamino)benzoyl)-3,4,5,6-tetrachlorobenzoic acid (16.28 g.), N,N,N',N'-tetraethyl-m-phenylenediamine (9.68 g.) and acetic anhydride (10 ml.) was heated (at 91° C.) during 2 hours. Addition of methanol (20 ml., then 12 ml., then 10 ml.) afforded 3-(2,4-bis-(diethylamino)phenyl)-3-(4-dimethylamino)phenyl)-4,5,6,7-tetrachlorophthalide (I: X = (CH3CH2)2N, Y2 = H, Y4 = (CH3)2N, Z4 = Z5 = Z6 = Z7 = Cl) in three fractions (m.p. 174°-176° C., m.p. 180°-181° C. and m.p. 180°-181° C.).

Provenance & Evidence