Direct Synthesis of Poly(adipate)Esters via Catalytic Isomerizing Dual Hydroesterificative Polymerization of...

Aliphatic polyesters, such as poly(adipate)esters, are attracting substantial attention as sustainable materials due to their degradability, recyclability, and versatility in various applications. However, the conventional production of poly(adipate)esters relies on energy-intensive processes and petroleum-derived adipic acid (AA), whose synthesis poses environmental concerns, including nitrous oxide emissions. Herein, we introduce a novel Pd-catalyzed isomerizing dual hydroesterificative polymerization (IDHP) strategy for direct poly(adipate)ester synthesis from readily available feedstocks of 1,3-butadiene, diols, and carbon monoxide. Key to success lay in the utilization of an electron-rich phosphine ligand with bulky steric hindrance, which efficiently facilitated linear-selective isomerizing hydroesterification. Mechanistic investigations revealed that the isomerizing hydroesterificative polymerization exhibited remarkable efficiency in producing poly(adipate)esters. The resulting poly(adipate)esters possess a similar structure compared to those produced by traditional polycondensation. With abundant feedstocks and atom-economy, this methodology provides a practical and eco-friendly approach to the production of poly(adipate)esters with varied microstructures.