Chiral Hydroxamic Ester-Enabled Asymmetric Catellani Reaction for the Synthesis of P-Stereogenic Phosphepine Oxides
Shao-Bai Yan1, Jin-Ying Shao2, Xian-Qi Hu2
1College of Chemistry and Chemical Engineering, Inner Mongolia University, 49 Xilinguole South Road, Hohhot 010020, China.
Abstract:
Asymmetric palladium/norbornene (NBE) cooperative catalysis is a powerful platform for assembling complex molecules. However, achieving enantiocontrol remains a fundamental challenge in cascades where the stereodetermining step occurs strictly after NBE extrusion. We report a conceptually distinct palladium-catalyzed annulation enabled by an exogenous chiral hydroxamic ester. This ligand remains coordinated to the palladium center throughout the catalytic cycle, affording diverse seven-membered P-stereogenic phosphepine oxides in moderate to good yields and up to 92% ee.
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