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Bicyclic pyrazolidinone derivatives from diastereoselective catalytic [3 + 3]-cycloaddition reactions of enoldiazoacetates with azomethine imines.

ABSTRACT: A highly regio- and diastereoselective synthesis of bicyclic pyrazolidinone derivatives by rhodium(II) acetate catalyzed [3 + 3]-annulation with enoldiazoacetates and azomethine imines has been achieved in high yield. A vinylogous reaction of the metal enol carbene with the azomethine imine initiates [3 + 3]-cycloaddition, whereas reaction at the carbene center effects N-N-cleavage of the azomethine imine.

SUBMITTER: Qian Y

PROVIDER: S-EPMC3663892 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Bicyclic pyrazolidinone derivatives from diastereoselective catalytic [3 + 3]-cycloaddition reactions of enoldiazoacetates with azomethine imines.

Qian Yu Y Zavalij Peter J PJ Hu Wenhao W Doyle Michael P MP

Organic letters 20130311 7

A highly regio- and diastereoselective synthesis of bicyclic pyrazolidinone derivatives by rhodium(II) acetate catalyzed [3 + 3]-annulation with enoldiazoacetates and azomethine imines has been achieved in high yield. A vinylogous reaction of the metal enol carbene with the azomethine imine initiates [3 + 3]-cycloaddition, whereas reaction at the carbene center effects N-N-cleavage of the azomethine imine. ...[more]

PMID: 23477672

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