Cl.CN(C)[C:4](=[CH:10][CH:11]=[C:12]([C:19]#[N:20])[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)[C:5]([O:7][CH2:8][CH3:9])=[O:6].C([OH:24])C>>[OH:24][C:4](=[CH:10][CH:11]=[C:12]([C:19]#[N:20])[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)[C:5]([O:7][CH2:8][CH3:9])=[O:6]1N aqueous hydrochloric acid solution (87 cc) is added in the course of 3 minutes to a solution, maintained under reflux, of ethyl 2-dimethylamino-5-cyano-5-phenyl-2,4-pentadienoate (21.3 g) in ethanol (27 cc). The mixture is cooled to a temperature of approximately 10° C. and the precipitate obtained is filtered off, washed with ethanol (15 cc) and dried. Ethyl 2-hydroxy-5-cyano-5-phenyl-2,4-pentadienoate (12.1 g), m.p. 189° C., is thereby obtained.
Wird geladen…