A Versatile Synthetic Platform for Discrete Oligo- and Polyesters Based on Optimized Protective Groups Via Iterative Exponential Growth

Discrete oligo- and polyesters are highly attractive for a wide range of investigations because of their great fidelity on structure-property relationships. Even though numerous synthetic approaches have been developed, a more versatile synthetic platform with broad group tolerance is still desired. Herein, we report an iterative exponential growth strategy for efficient synthesis of discrete oligo- and polyesters, employing an optimized protective group pair, namely, TBDPS ether and t-butyl ester. The versatility of the strategy is demonstrated by facile preparation of several structurally diverse discrete oligo- and polyesters under mild, safe, and scalable reaction conditions, with the number of repeat units up to 256. Moreover, the contributions of the terminal protective groups on the melting and crystallization behaviors of discrete oligo- and poly(epsilon-caprolactone)s were investigated. With this robust synthetic platform, various functional moieties can be readily incorporated into polyester chains, and a myriad of applications of polyesters could thus be reasonably anticipated.