Studies on regioselective acylation of cellulose with bulky acid chlorides

The regioselective esterification of cellulose by reaction with bulky acyl halides including pivaloyl chloride, adamantoyl chloride and 2,4,6-trimethylbenzoyl chloride was studied. Functionalization conditions to achieve a given degree of substitution (DS) and the resulting ester substitution pattern were described in detail. One- and two-dimensional NMR spectroscopy techniques were used to confirm the structure of the esters obtained. We compared the effects on substitution of using different esterifying reagents and solvent systems including DMAc/LiCl, DMSO/TBAF, and ionic liquids (ILs).