Selective electrochemical C-O bond cleavage of β-O-4 lignin model compounds mediated by iodide ion

The electrochemically oxidative cleavage of lignin beta-O-4 model compounds mediated by iodide ion has been studied. The results indicate that electrolytic conditions play a predominant role in determining the distribution of cleavage products. The preparative-scale electrolysis proceeds in a simple undivided cell, employing a catalytic amount of Nal as the redox mediator and supporting electrolyte in methanol. Under these conditions, the C-beta-O bond is selectively cleaved with 2,2-dimethoxy-2-arylacetaldehyde being the main product. In some cases, the reaction gives a good yield of cleavaged products. The results further demonstrate that the indirect electrolysis mediated by halide is a versatile approach for chemical transformation. (C) 2017 Elsevier Ltd. All rights reserved.