Acylation of cellulose with carboxylic acids

Acylation of cellulose with carboxylic acids in the pyridine (Py) system, containing p-toluenesulfonyl chloride (TsCl), was investigated. As with the acetic acid (AcOH), almost trisubstituted cellulose esters were obtained by this system, even in the cases of higher aliphatic acids and benzoic acid. A complex formation was observed when mixing Py, TsCl and carboxylic acid and was identified as pyridinium p-toluenesulfonate which was important in considering the reaction mechanism. DMF was also attempted instead of Py, and found out to be more effective for acetylation