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A number of 4'—0-monoalkylated bisphenyl (5—5') type lignin model compounds was synthesized from dchydrodivanillin (5) by way of 4—0-acetyldehydrodivanillin (6). The 13C NMR spectral characteristics of the compounds synthesized verified the usefulness of the generalized substituent chemical shift (SCS) additivity rule elucidated for estimation of the 13C chemical shift of aromatic carbons in 5—5'type model compounds and probably in 5—5'type substructures in lignins. In addition, preliminary results from a kinetic study on the selective 0-acetylation of dehydrodivanillin (5) showed that 4—0-acetyldehydrodivanillin (6) was produced äs the major product, more than 75% of the products isolated from the reaction mixture, when a mixture consisting of compound 5, acetic anhydride and pyridine in the molar ratio of approximately 1: 1: 19 was stirred at room temperature for 20 minutes. Asmall amount of 4, 4'—0 …