Synthesis and Some Transformations of 2-(3-Amino-1-Phenylpropyl)furan

Abstract

A preparative method was developed for the synthesis of ethyl furfurylidenecyanoacetate. Its condensation with phenylmagnesium bromide gave ethyl α-cyano-β-(2-furyl)hydrocinnamate, the decarboxylation of which led to β-(2-furyl)hydrocinnamonitrile. Reduction of this nitrile with lithium aluminum hydride gave 2-(3-amino-1-phenylpropyl)furan. Some of its transformations were studied.In a continuation of our research [1, 2] by the reaction of ethyl furfurylidenecyanoacetate (1) with phenylmagnesium bromide we obtained ethyl α-cyano-β-(2-furyl)hydrocinnamate (2), in the molecule of which there are simultaneously phenyl and furyl radicals at the asymmetric carbon atom. Its decarbethoxylation led to β-(2-furyl)hydrocinnamonitrile (3), while reduction of the latter with lithium aluminum hydride in ether or tetrahydrofuran gave 2-(3-amino-1-phenylpropyl)furan (4). Condensation of the amine 4 with various aromatic aldehydes and ketones gave the corresponding azomethines, which were reduced by sodium borohydride without isolation to the secondary amines 5-13. With the chlorides of various acids the amides 14-16 were obtained, and with succinic and phthalic anhydrides substituted succinimide 17 and phthalimide 18 were obtained.