Acid promoted C–C bond oxidative cleavage of β-O-4 and β-1 lignin models to esters over a copper catalyst

Abstract

Depolymerisation of lignin to aromatics is a challenging task. We herein report that a Cu(OAc)₂/BF₃·OEt₂ catalyst is effective in simultaneously cleaving C–C bonds in β-1 and β-O-4 ketones, yielding esters and phenols. In-depth studies show that C–H bond activation is the rate determining step for C–C bond cleavage. BF₃·OEt₂ promotes the reaction via activating the β-C–H bond. This study offers the potential to obtain aromatic esters from lignin.