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N-heterocyclic carbene-catalyzed rearrangements of vinyl sulfones.

ABSTRACT: N-heterocyclic carbenes catalyze the rearrangement of 1,1-bis(arylsulfonyl)ethylene to the corresponding trans-1,2-bis(phenylsulfonyl) under mild conditions. Tandem rearrangement/cycloadditions have been developed to capitalize on this new process and generate highly substituted isoxazolines and additional heterocyclic compounds. Preliminary mechanistic studies support a new conjugate addition/Umpolung process involving the ejection and subsequent unusual re-addition of a sulfinate ion.

SUBMITTER: Atienza RL

PROVIDER: S-EPMC3309460 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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N-heterocyclic carbene-catalyzed rearrangements of vinyl sulfones.

Atienza Roxanne L RL Roth Howard S HS Scheidt Karl A KA

Chemical science 20110610 9

N-heterocyclic carbenes catalyze the rearrangement of 1,1-bis(arylsulfonyl)ethylene to the corresponding trans-1,2-bis(phenylsulfonyl) under mild conditions. Tandem rearrangement/cycloadditions have been developed to capitalize on this new process and generate highly substituted isoxazolines and additional heterocyclic compounds. Preliminary mechanistic studies support a new conjugate addition/Umpolung process involving the ejection and subsequent unusual re-addition of a sulfinate ion. ...[more]

PMID: 22448316

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