Chiral Dinucleating Salan-Type Phosphine Ligands for Asymmetric Allylic Alkylations with α-Cyano Ketones
Peng Li1, Yi-Hao Zhang1, Sai Wang1
1Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, State Key Laboratory of Polyolefins and Catalysis, Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
Abstract:
While chiral dinuclear catalysts have emerged as a powerful strategy to overcome the inherent limitations of monometallic systems in terms of stereocontrol and reactivity, the development of chiral dinucleating phosphine ligands has been less explored. Guided by the principle of dinuclear cooperative activation, we developed a new class of chiral dinucleating phosphine ligands based on a salan-type scaffold. The catalytic utility of these ligands was demonstrated through their successful application in a Ni/Pd heterobimetallic system for asymmetric allylic alkylations with α-cyano ketones and esters. This methodology enables the efficient construction of nitrile compounds bearing quaternary stereocenters.
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