Derivatization Followed by Reductive Cleavage (DFRC Method), a New Method for Lignin Analysis:  Protocol for Analysis of DFRC Monomers

A new method for selective and efficient cleavage of arylglycerol−β-aryl (β-O-4) ether linkages in lignins is introduced. The acronym “DFRC” relates to the reactions involved, d erivatization f ollowed by r eductive c leavage. Derivatization, accompanied by cell wall solubilization, is accomplished with acetyl bromide in acetic acid; reductive cleavage of resulting β-bromo ethers utilizes zinc in an acidic medium. Following acetylation, degradation monomers (4-acetoxycinnamyl acetates) are quantified by GC, providing data analogous to those from analytical thioacidolysis. Keywords: Acetyl bromide; lignin; β-aryl ether; thioacidolysis; reductive elimination