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Updated: Jun 18, 2026

Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
Published on: November 12, 2016
Switching the Spin State of Ni Catalysts Promotes Regiodivergent Reactions
Yuanlin Wang1, Chenxi Zhang1, Lu Zhang1
1Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, State Key Laboratory of Synergistic Chem-Bio Synthesis, Zhengzhou Industrial Technology Research Institute of Shanghai Jiao Tong University, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Abstract:
Spin state, a variable factor at the electronic level, plays a significant role in determining the properties of metal complexes. However, the variability of the spin state has largely been regarded as a phenomenon to explain reaction mechanisms rather than as a chemical tool for controlling reaction selectivity. Herein, we report a nickel-catalyzed regiodivergent allylic substitution reaction of vinyl epoxides with styrylboronic acids, where the regiodivergence is directed by switching the spin state of the nickel catalysts. Linear and branched skipped diene alcohols were synthesized with broad substrate compatibility. Additionally, the enantioconvergent synthesis of branched products from racemic vinyl epoxides was achieved through dynamic kinetic asymmetric transformation. Mechanistic investigations confirmed the critical role of coordination modes with varying spin states of the nickel catalysts in achieving regiodivergence.
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