One-pot solvent-free microwave-assisted aza-Michael addition reaction of acrylonitrile

Abstract

A novel and highly effective one-pot microwave-assisted aza-Michael addition reaction of acrylonitrile, as Michael acceptor with various primary aliphatic and aromatic amines, as Michael donor has been reported. The reaction was catalyzed by a cost-effective, highly efficient and eco-friendly catalyst, molecular sieve of 4 A0 size, under solvent-free conditions. A detail investigation on reaction controlling parameters like reaction timing and amount of catalyst was studied. The plausible mechanistic pathway has been proposed for the formation of acrylonitrile adducts. The identity of the synthesized products was established by conventional spectroscopic techniques FT-IR, 1H and 13C{1H} NMR, ESI-MS and DLS measurements. DLS result shows hydrodynamic diameter of lower alkyl chain in the range of 200–300 nm and for higher alkyl chain around 1 μm. Sheldon's hot filtration test confirms the significance of the catalyst and their heterogeneity was also confirmed by recycling it for five consecutive cycles without any noticeable change in the yield.