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 -Me-DBO. ()-bearing bulkier binaphthyl units accomplished moderate isoselectivity via kinetic resolution polymerization, affording P(Me-BDO) with a 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 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.
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