Green and one-pot synthesis of tetrahydropyridine derivatives using tetramethylguanidinium acetate as a reusable ionic liquid catalyst

Abstract

A simple and efficient method has been presented for the synthesis of tetrahydropyridine derivatives via one-pot reaction of aromatic amines (2 eqv), β-ketoesters (1 eqv) and aromatic aldehydes (2 eqv) in the presence of N,N,N′,N′-tetramethylguanidinium acetate [TMG][Ac]. The reaction was carried out in EtOH under reflux conditions. Some of the advantages of this procedure are green and safe solvent, high atom economy, high yield, and no need to column chromatography for product purification. Moreover, the catalyst is recyclable and can be used up to four times without significant loss of its activity.

Keywords

• tetrahydropyridine
• green chemistry
• tetramethylguanidinium acetate
• ionic liquid
• reusable catalyst