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Zn-ProPhenol Catalyzed Enantioselective Mannich Reaction of 2-Azirines with Alkynyl Ketones. | LitMetric

Zn-ProPhenol Catalyzed Enantioselective Mannich Reaction of 2-Azirines with Alkynyl Ketones.

Org Lett

Department of Chemistry, Stanford University, Stanford, California 94305-5080, United States.

Published: December 2020

The enantioselective Mannich reaction of 2-azirines with alkynyl ketones is achieved under Zn-ProPhenol catalysis, delivering various aziridines with vicinal tetrasubstituted stereocenters in high yields with excellent enantioselectivities. The bimetallic Zn-ProPhenol complexes activate both the nucleophile and the electrophile in the same chiral pocket. A unique intramolecular hydrogen bond is observed in the obtained Mannich adducts, which lowers the basicity of the product's aziridine nitrogen thus favoring enantioselective control and allowing catalyst turnover.

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http://dx.doi.org/10.1021/acs.orglett.0c03737DOI Listing

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