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Use of a new spirophosphine to achieve catalytic enantioselective [4 + 1] annulations of amines with allenes to generate dihydropyrroles.

ABSTRACT: Due in part to the common occurrence of five-membered nitrogen heterocycles in bioactive molecules, the discovery of methods for the enantioselective synthesis of such structures is a useful endeavor. Building on a single example by Tong of a phosphine-catalyzed [4 + 1] annulation of an amine with an allene that furnished an achiral dihydropyrrole in 22% yield, we have developed, with the aid of a new chiral spirophosphine catalyst, a method with increased utility, specifically, improved yield, enhanced scope (the use of ?-substituted allenes), and good ee. The enantioenriched dihydropyrrole products can be transformed into other interesting families of compounds with very good stereoselectivity.

SUBMITTER: Kramer S

PROVIDER: S-EPMC4433051 | biostudies-other | 2015 Mar

REPOSITORIES: biostudies-other

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Use of a new spirophosphine to achieve catalytic enantioselective [4 + 1] annulations of amines with allenes to generate dihydropyrroles.

Kramer Søren S Fu Gregory C GC

Journal of the American Chemical Society 20150317 11

Due in part to the common occurrence of five-membered nitrogen heterocycles in bioactive molecules, the discovery of methods for the enantioselective synthesis of such structures is a useful endeavor. Building on a single example by Tong of a phosphine-catalyzed [4 + 1] annulation of an amine with an allene that furnished an achiral dihydropyrrole in 22% yield, we have developed, with the aid of a new chiral spirophosphine catalyst, a method with increased utility, specifically, improved yield, ...[more]

PMID: 25780940

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