Production of alpha-alkylcinnamic aldehyde

PROBLEM TO BE SOLVED: To provide a method for producing the subject compound in high selectivity and in large productivity, enabling the progress of the reaction in a solvent-free state, by using pyrrolidine as a catalyst. SOLUTION: This method for producing an alpha-alkylcinnamic aldehyde comprises subjecting (A) benzaldehyde and (B) an alkanal to an aldol condensation reaction in the presence of a base as a catalyst. Therein, (C) pyrrolidine is used as the catalyst. The component B is preferably a compound of the formula: R-CH 2 -CHO (R is a 4-10C alkyl), especially n-octanal. The condensation reaction is preferably carried out by reacting the component A with the component B in a molar ratio of 1:(1.2-1.8) in the presence of an acid, especially octanoic acid and/or acetic acid, in the absence of a solvent at 80-90°C, while the component B is gradually introduced to the reaction mixture of the component A with the component C. COPYRIGHT: (C)1997,JPO