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Enantioselective Formal ?-Methylation and ?-Benzylation of Aldehydes by Means of Photo-organocatalysis.

ABSTRACT: Detailed herein is the photochemical organocatalytic enantioselective ?-alkylation of aldehydes with (phenylsulfonyl)alkyl iodides. The chemistry relies on the direct photoexcitation of enamines to trigger the formation of reactive carbon-centered radicals from iodosulfones, while the ground-state chiral enamines provide effective stereochemical control over the radical trapping process. The phenylsulfonyl moiety, acting as a redox auxiliary group, facilitates the generation of radicals. In addition, it can eventually be removed under mild reducing conditions to reveal methyl and benzyl groups.

SUBMITTER: Filippini G

PROVIDER: S-EPMC5396335 | biostudies-other | 2017 Apr

REPOSITORIES: biostudies-other

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Enantioselective Formal α-Methylation and α-Benzylation of Aldehydes by Means of Photo-organocatalysis.

Filippini Giacomo G Silvi Mattia M Melchiorre Paolo P

Angewandte Chemie (International ed. in English) 20170321 16

Detailed herein is the photochemical organocatalytic enantioselective α-alkylation of aldehydes with (phenylsulfonyl)alkyl iodides. The chemistry relies on the direct photoexcitation of enamines to trigger the formation of reactive carbon-centered radicals from iodosulfones, while the ground-state chiral enamines provide effective stereochemical control over the radical trapping process. The phenylsulfonyl moiety, acting as a redox auxiliary group, facilitates the generation of radicals. In addi ...[more]

PMID: 28323367

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