An Affordable and Eco-friendly Method for Pseudo-five-component Synthesis of Tetrahydropyridines Using Gum Arabic-OPO3H2 as a Natural-based Catalyst

Abstract

This study describes a facile and environmentally friendly protocol for the synthesis of highly functionalized tetrahydropyridines via pseudo-five-component reaction of aromatic aldehydes, amines and ethyl acetoacetate using GA-OPO3H2 as catalyst. In addition to the easy preparation of GA-OPO3H2 from bio-renewable materials, this catalyst can also be recycled and reused without obvious loss of catalytic activity. The synthesis of tetrahydropyridines via this new green methodology offers significant advantages in terms of no use of a solvent, no hazardous waste, uncomplicated work-up and high yields of products.