Abstract: Disclosed herein are methods and compositions of matter showing that catalytic autoxidation can be used to generate aromatic monomers from C—C linked dimers and oligomers derived from lignin. This is demonstrated by acetylating phenol-rich RCF oil and then conducting aerobic oxidation of the oligomeric fraction of poplar RCF oil with a Co/Mn/Br catalyst mixture in acetic acid. This reaction yields a collection of oxygenated aromatic monomers that represent a 17% increase in monomer yield compared to the RCF process alone.