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Stereoselective cascade reactions that incorporate a 7-exo acyl radical cyclization.

ABSTRACT: [reaction: see text] Radical cascades that feature a 7-exo acyl radical cyclization followed by a 6-exo or 5-exo alkyl radical cyclization proceed with very good yields and diastereoselectivities. Two stereocenters are created by the reaction, and a single isomeric product was obtained from each of the five substrates examined. The relative configurations of the products are consistent with cyclizations occurring via chairlike or pseudochairlike transition states.

SUBMITTER: Grant SW

PROVIDER: S-EPMC2517416 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature

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Stereoselective cascade reactions that incorporate a 7-exo acyl radical cyclization.

Grant Seth W SW Zhu Koudi K Zhang Yu Y Castle Steven L SL

Organic letters 20060401 9

[reaction: see text] Radical cascades that feature a 7-exo acyl radical cyclization followed by a 6-exo or 5-exo alkyl radical cyclization proceed with very good yields and diastereoselectivities. Two stereocenters are created by the reaction, and a single isomeric product was obtained from each of the five substrates examined. The relative configurations of the products are consistent with cyclizations occurring via chairlike or pseudochairlike transition states. ...[more]

PMID: 16623571

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