Visible-light-induced C-C bond cleavage of lignin model compounds with cyanobenziodoxolone

[Display omitted] •A C-C bond cleavage approach of β-O-4 lignin model compounds was developed.•Unexpected acetal esters were obtained.•A variety of β-O-4 lignin model compounds could be converted into aldehydes.•Exited state of Ir (III) catalyst could be quenched by CBX. The catalytic degradation of lignin to value-added chemicals has received considerable attention over the past decade. Photocatalysis provides promising approaches to enable previously inaccessible transformations. However, examples of the visible-light promoted degradation of lignin are still limited. In this work, the visible-light-induced selective C-C bond cleavage of β-O-4 lignin model compounds has been disclosed via β-scission of in situ generated alkoxy radical intermediates. With cyanobenziodoxolone as the oxidant, a variety of substrates could be transformed into aldehydes in moderate to good yields. In addition, unexpected acetal esters which could conveniently furnish formaldehyde and phenols by alcoholysis were observed.