Chitosan: highly efficient, green, and reusable biopolymer catalyst for the synthesis of alkylaminophenols via Petasis borono–Mannich reaction

Abstract

We screened the catalytic efficacy of different functionalized polymeric catalysts such as nafion® 117, PEG-OSO3H, tween® 80, poly styrene –SO3H and chitosan for the preparation of alkylaminophenols through Petasis borono–Mannich reaction by one-pot three component condensation of o-hydroxy aldehydes, secondary amines, and various boronic acids. It was observed that the reaction was completed in a short period of time and the yield was optimum by virtue of chitosan heterogeneous catalyst. Furthermore, the catalyst can be recovered by simple filtration and reused up to ten cycles. Smooth loss of catalytic activity was observed from the 6th cycle of reuse.