1960 年 80 巻 1 号 p. 37-41
N-Furfurylidenne-amines (Table I), N-(5-methylfurfurylidene)-amines (Table II), and N-(5-nitrofurfurylidene)-amines (Table III) were prepared respectively from furfural, 5-methylfurfural, and 5-nitrofurfural. Condensation of furfural and 5-methylfurfural with the amine was more difficult than with 5-nitrofurfural. N-(5-Nitrofurfurylidene)-amines so obtained did not show the deep purple coloration with aniline hydrochloride. Application of aliphatic primary amines as hydrochloride to N-(furfurylidene)-alkyl-amines (E′) failed to cause any reaction, but application of 2 moles of aromatic amine hydrochlorides to 1 mole of the furan compound resulted in facile reaction to form the Stenhouse dye (B) in quantitative yield. On the other hand, application of 1 mole of the amine or 1 mole each of aromatic amine and its hydrochloride to 1 mole of the furan compound resulted in separation of the aliphatic amine constituting the furan compound as its hydrochloride. N-Furfurylidene-alkylamine did not react with aromatic amine itself.