Ruthenium-catalyzed C-C bond cleavage in lignin model substrates.

Ruthenium-triphos complexes exhibited unprecedented catalytic activity and selectivity in the redox-neutral C-C bond cleavage of the β-O-4 lignin linkage of 1,3-dilignol model compounds. A mechanistic pathway involving a dehydrogenation-initiated retro-aldol reaction for the C-C bond cleavage was proposed in line with experimental data and DFT calculations.