Caro's Acid–Silica Gel: An Efficient and Versatile Catalyst for the One-Pot Synthesis of Tetrahydrobenzo[<i>b</i>]pyran Derivatives

Abstract

An efficient one-pot synthesis of tetrahydrobenzo[b]pyran is described. This involved the three-component reaction of aromatic aldehydes, molononitrile, and dimedone in the presence of a catalytic amount of Caro's acid supported on silica gel in ethanol/water under reflux.