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Organocatalytic Asymmetric Decarboxylative Mannich Reaction of β-Keto Acids with Cyclic α-Ketiminophosphonates: Access to Quaternary α-Aminophosphonates. | LitMetric

Organocatalytic Asymmetric Decarboxylative Mannich Reaction of β-Keto Acids with Cyclic α-Ketiminophosphonates: Access to Quaternary α-Aminophosphonates.

Org Lett

Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, and Tianjin Collaborative Innovation Center of Chemical Science & Engineering , Tianjin University, Tianjin 300072 , P. R. China.

Published: June 2018

An organocatalytic asymmetric decarboxylative Mannich reaction of β-keto acids with cyclic α-ketiminophosphonates has been developed. By using saccharide-derived bifunctional amine-thiourea catalysts bearing an axial chiral binaphthyl scaffold, a wide range of quaternary α-amino-γ-oxophosphonates were obtained in up to 93% yield and >99% ee. Furthermore, two interesting α-aminophosphonate derivatives were synthesized from the corresponding decarboxylative Mannich product via simple transformations.

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http://dx.doi.org/10.1021/acs.orglett.8b01422DOI Listing

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