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Photocatalytic [2 + 2] cycloadditions of enones with cleavable redox auxiliaries.

ABSTRACT: ?,?-Unsaturated 2-imidazolyl ketones undergo [2 + 2] cycloaddition with a variety of Michael acceptors upon irradiation with visible light in the presence of Ru(bpy)(3)(2+). Cleavage of the imidazolyl auxiliary from the cycloadducts affords cyclobutane carboxamides, esters, thioesters, and acids that would not be accessible from direct cycloaddition of the corresponding unsaturated carbonyl compounds.

SUBMITTER: Tyson EL

PROVIDER: S-EPMC3288794 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Photocatalytic [2 + 2] cycloadditions of enones with cleavable redox auxiliaries.

Tyson Elizabeth L EL Farney Elliot P EP Yoon Tehshik P TP

Organic letters 20120209 4

α,β-Unsaturated 2-imidazolyl ketones undergo [2 + 2] cycloaddition with a variety of Michael acceptors upon irradiation with visible light in the presence of Ru(bpy)(3)(2+). Cleavage of the imidazolyl auxiliary from the cycloadducts affords cyclobutane carboxamides, esters, thioesters, and acids that would not be accessible from direct cycloaddition of the corresponding unsaturated carbonyl compounds. ...[more]

PMID: 22320352

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