Efficient Access to Sequence-Controlled Poly(α-hydroxy acids) with Ax(BC)yDz-Type and Ax(BC)yAz-Type Triblock Structures via Self-Switchable Ring-Opening Polymerization of Monomer Mixtures

Zhaowei Jia; Xiaofei Zhang; Ji Xian; Chixian He; Hongjun Fu; Luya Cao; Xiaobo Pan; Jincai Wu

doi:10.1021/acsmacrolett.3c00211

Efficient Access to Sequence-Controlled Poly(α-hydroxy acids) with A_x(BC)_yD_z-Type and A_x(BC)_yA_z-Type Triblock Structures via Self-Switchable Ring-Opening Polymerization of Monomer Mixtures

ACS Macro Lett. 2023 Jun 20;12(6):710-718. doi: 10.1021/acsmacrolett.3c00211. Epub 2023 May 17.

Authors

Zhaowei Jia¹, Xiaofei Zhang¹, Ji Xian¹, Chixian He^{1

2}, Hongjun Fu¹, Luya Cao^{1

3}, Xiaobo Pan¹, Jincai Wu¹

Affiliations

¹ State Key Laboratory of Applied Organic Chemistry (Lanzhou University), Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China.
² College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, People's Republic of China.
³ State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization, Baotou Research Institute of Rare Earths, Baotou 014030, People's Republic of China.

PMID: 37195102
DOI: 10.1021/acsmacrolett.3c00211

Abstract

Synthesizing block-sequence-controlled poly(α-hydroxy acids) of three or four α-hydroxy acids remains challenging in one step. In this study, a strategy was employed using three monomers of O-carboxyanhydrides (OCAs) consisting of one α-hydroxy acid (A), asymmetric cyclic diester (B and C, two different α-hydroxy acids of B and C), and symmetric cyclic diester (one α-hydroxy acid of D) with remarkably different activities toward a stereoselective, regioselective, and chemoselective initiator of a zirconium complex. Then, via a self-switchable approach, these monomers can be copolymerized in a well-controlled block sequence of A_x(BC)_yD_z and A_x(BC)_yA_z without an external stimulus. Moreover, upon addition of more monomer mixtures during the copolymerization process, more complicated sequence-controlled poly(α-hydroxy acids) can be achieved with up to 15 blocks.