Organocatalytic synthesis of sugar-derived polyesters via ring-opening alternating copolymerization of anhydrosugar oxetane and anhydrides

In this work, the organocatalytic strategy for the ring-opening copolymerization (ROCOP) of 3,5-anhydro-D-xylose oxetane 1 and various anhydrides has been demonstrated by use of phosphazene base (P1) and triethyl borane (TEB). The ROCOP proceeds efficiently to generate sugar-derived polyesters with perfectly alternating sequence distribution, controlled molar masses, and moderate dispersity. These polyesters show good thermal stability (T-max > 320 degrees C) and adjustable glass transition temperatures (T-g 70 similar to 110 degrees C) with the variation of anhydrides. This work provides efficient organocatalyst for the selective copolymerization for biomass-derived degradable polyesters.