四川大学朱剑波团队报道了溶解度平衡辅助动力学分解聚合制备含轴向手性的等规聚酯。相关研究成果发表在2024年12月16日出版的《美国化学会杂志》。

对聚合物立体化学的高水平控制利用了材料性能的微调，但这在合成聚合物化学中仍然是一个艰巨的挑战。

研究人员制备了一类新型的带有轴向手性联萘部分的盐钇催化剂，用于rac-Me-DBO的轴向立体控制聚合。（S） -含Y3的大块联萘单元通过动力学拆分聚合实现了适度的等选择性，提供了Pm高达0.80的P（Me-BDO）。

值得注意的是，利用溶解度平衡来保持溶液状态下两个对映体纯单体对的浓度恒定，有助于提高聚合的等选择性，并提供了Pm高达0.93的全同立构P（Me-DBO）产品。详细的机理研究验证了溶解度平衡转移假说。

该溶解度平衡辅助的动力学拆分聚合策略有望成为一种多功能平台，在不重新设计催化剂的情况下改善立体控制。

附：英文原文

Title: Solubility-Equilibrium-Assisted Kinetic Resolution Polymerization toward Isotactic Polyesters Containing Axial Chirality

Author: Qing Cao, Hua-Zhong Fan, Min Xie, Zhongzheng Cai, Jian-Bo Zhu

Issue&Volume: December 16, 2024

Abstract: High-level control over polymer stereochemistry leverages the fine-tuning of material properties, but it is still a formidable challenge in synthetic polymer chemistry. Herein we prepared a new class of salph yttrium catalysts bearing axially chiral binaphthyl moieties for axially stereocontrolled polymerization of rac-Me-DBO. (S)-Y3-bearing bulkier binaphthyl units accomplished moderate isoselectivity via kinetic resolution polymerization, affording P(Me-BDO) with a Pm of up to 0.80. Remarkably, exploiting the solubility equilibrium to maintain a constant for the concentration of two enantiopure monomer pairs in the solution state contributed to a boost in polymerization isoselectivity and furnished isotactic P(Me-DBO) products with a Pm of up to 0.93. Detailed mechanistic investigations supported our solubility-equilibrium shifting hypothesis. This solubility-equilibrium-assisted kinetic resolution polymerization strategy was expected to become a versatile platform to improve stereocontrol without de novo catalyst design.

DOI: 10.1021/jacs.4c14778

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c14778