1953 年 73 巻 7 号 p. 716-719
The catalyst system used in the condensation of 5-nitrofurfural and acetaldehyde was considered as a basic and an acidic components. Piperidine, diethylaminoethanol, diethanolamine, and pyridine were selected for the former and acetic, tartaric, citric, succinic, maleic, valeric, and 5-nitrofuroic acids for the latter. A catalyst system was made by the combination of the two components and the condensation was carried out in benzene solution under a mild temperature conditions. 2-(5-Nitro)-furylacrolein, m. p. 118°, was obtained in 49% yield by the use of piperidine-acetic acid system and in 50% yield by the use of piperidine-5-nitrofuroic acid system. It was assumed that the electrophilic piperidinium ion, rather than the nucleophilic piperidine, took part in the catalytic action in this condensation.