N,N-Dimethylaniline → 4-(Dimethylamino)Benzaldehyde

Participants

Reaction Steps

N,N-Di(loweralkyl)anilines, preferably N,N-dimethyl aniline, are reacted with phosphorus oxychloride in dialkyl formamide, preferably dimethyl formamide (DMF), according to the Vilsmeier Reaction to give 4-(N,N-di-loweralkylamino)benzaldehydes, preferably 4-(N,N-dimethylamino)benzaldehyde. The reaction is conducted using essentially two molar proportions of the N,N-dialkylaniline, essentially one molar proportion (or a slight excess) of phosphorus oxychloride, and essentially two molar proportions (or a slight excess) of dimethyl formamide. The phosphorus oxychloride is slowly added, with cooling, to the mixture of N,N-dialkylaniline and dimethyl formamide, keeping the temperature in the range of about 50°-70° C., preferably about 55°-65° C. The 4-(di-loweralkylamino)benzaldehyde thus formed may be isolated at this point for subsequent reaction with an N,N-di(loweralkyl)aniline and the sulfinic acid or the reaction may be continued without isolation in what is referred to herein as the "in situ" process.

Provenance & Evidence