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Photoredox activation for the direct ?-arylation of ketones and aldehydes.

ABSTRACT: The direct ?-activation of saturated aldehydes and ketones has long been an elusive transformation. We found that photoredox catalysis in combination with organocatalysis can lead to the transient generation of 5?-electron ?-enaminyl radicals from ketones and aldehydes that rapidly couple with cyano-substituted aryl rings at the carbonyl ?-position. This mode of activation is suitable for a broad range of carbonyl ?-functionalization reactions and is amenable to enantioselective catalysis.

SUBMITTER: Pirnot MT

PROVIDER: S-EPMC3723331 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Photoredox activation for the direct β-arylation of ketones and aldehydes.

Pirnot Michael T MT Rankic Danica A DA Martin David B C DB MacMillan David W C DW

Science (New York, N.Y.) 20130301 6127

The direct β-activation of saturated aldehydes and ketones has long been an elusive transformation. We found that photoredox catalysis in combination with organocatalysis can lead to the transient generation of 5π-electron β-enaminyl radicals from ketones and aldehydes that rapidly couple with cyano-substituted aryl rings at the carbonyl β-position. This mode of activation is suitable for a broad range of carbonyl β-functionalization reactions and is amenable to enantioselective catalysis. ...[more]

PMID: 23539600

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