Simple synthesis of mixed cellulose acylate phosphonates applying n-propyl phosphonic acid anhydride

Cellulose mixed esters containing alkylphosphonate and carboxylate groups were prepared homogeneously by a new one-pot method using n-propyl phosphonic acid anhydride (T3P(A (R))) in LiCl/N-methyl-2-pyrrolidone (NMP). n-Propyl phosphonic acid anhydride acts as both an activating agent for carboxylic acids and phosphonation reagent. Cellulose mixed esters with DSacyl ranging from 1.4 to 1.8, and DSphos up to 0.7 could be prepared. The structure of the cellulose mixed esters was elucidated by FTIR- and NMR spectroscopy, as well as by GPC and solubility tests.