Selective cleavage of the Cα–Cβ linkage in lignin model compounds via Baeyer–Villiger oxidation†
Abstract
Lignin is an amorphous aromatic polymer derived from plants and is a potential source of fuels and bulk chemicals. Herein, we present a survey of reagents for selective stepwise oxidation of lignin model compounds. Specifically, we have targeted the oxidative cleavage of Cα–Cβ bonds as a means to depolymerize lignin and obtain useful aromatic compounds. In this work, we prepared several lignin model compounds that possess structures, characteristic reactivity, and linkages closely related to the parent lignin polymer. We observed that selective oxidation of benzylic hydroxyl groups, followed by Baeyer–Villiger oxidation of the resulting ketones, successfully cleaves the Cα–Cβ linkage in these model compounds.