The present paper describes the chloroformate activation of pullulan by reaction with 4-nitrophenyl chloroformate. N.m.r. analysis indicated that the ester formation takes place preferentially at the C6 hydroxy groups of pullulan. It was further demonstrated that activation gives linear carbonates, aliphatic carbonates including cyclic five-membered carbonates, and non-strained aliphatic carbonates. All of these carbonates react with amines to yield the corresponding urethane derivatives. The 4-nitrophenyl chloroformate activation of pullulan is an easy method for obtaining amine-containing pullulan derivatives.
Посилання на статтю:
Chemical modification of pullulan: 2. Chloroformate activation / Dorine Bruneel and Etienne Schacht* // Polymer. – 1993. – Vol 34. – P. 2633-2637.