Sorbic Acid as a Renewable Resource for Atom-Economic and Selective Production of <i>p</i>-Toluic Acid and Alkyl-<i>p</i>-Toluates: Intermediates to Bioterephthalic Acid and Esters

Abstract

A new pathway for the production of p-toluic acid and alkyl-p-toluates is described here, starting from industrially relevant but underexploited renewable sorbic acid. A simple optimized Diels–Alder reaction between sorbic acid esters and ethylene, followed by aromatization, afford a full selectivity to para-substituted toluates. p-Toluates and hydrolyzed p-toluic acid are industrial terephthalic and terephthalates precursors, which are major commodity chemicals in the packaging and fiber industries after copolymerization with diols.