Synthesis of side-chain functional Poly(ε-caprolactone) via the versatile and robust organo-promoted esterification reaction

Side-chain functionalized poly( ε -caprolactone) (PCL) is of much ongoing interest in light of its biocompatible and biodegradable features being widely applied in the field of biomaterials, but the versatile and robust protocols for the preparation of PCL-based (co)polymers with functional pendants remaining a challenge. Herein, an organic base of tetramethylguanidine (TMG) promoted esterification reaction of a variety of carboxylic acids and a -Cl of poly( α -chloro- ε -caprolactone) (P( α- Cl - CL)), enabling the direct synthesis of side-chain functional PCL, is described with wide substrate scope in mild reaction condition. It is noteworthy that this protocol affords one versatile and robust method for the preparation of PCL-based functional polymers, which are of high attraction for their application in biological area.