Enzyme-Inspired Chiral Secondary-Phosphine-Oxide Ligand with Dual Noncovalent Interactions for Asymmetric
Caiyou Chen1, Zhefan Zhang1, Shicheng Jin1
1College of Chemistry and Molecular Sciences, Wuhan University, 430072, Wuhan, P.R. China.
Abstract:
Inspired by the unique character of enzymes, we developed novel chiral SPO (secondary-phosphine-oxide) ligand (SPO-Wudaphos) which can enter into both ion pair and H-bond noncovalent interactions. The novel chiral SPO-Wudaphos exhibited excellent results in the asymmetric hydrogenation of α-methylene-γ-keto carboxylic acids, affording the chiral γ-keto acids with up to over 99 % ee. A series of control experiments and DFT calculations were conducted to illustrate the critical roles of both the ion pair and H-bond noncovalent interactions.
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