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Remote stereoinduction in the acylation of fully substituted enolates: tandem Reformatsky/quaternary Claisen condensations of silyl glyoxylates and ?-lactones.

ABSTRACT: Reformatsky reagents react sequentially with silyl glyoxylates and ?-lactones to give highly functionalized Claisen condensation products. A heretofore undocumented instance of stereochemical 1,4-induction results in efficient transmission of ?-lactone stereochemistry to the emerging fully substituted stereocenter. Second-stage transformations reveal that the five heteroatom-containing functionalities embedded within the products are entirely chemo-differentiated, a circumstance that permits rapid assembly of the leustroducsin B core substructure.

SUBMITTER: Greszler SN

PROVIDER: S-EPMC3056164 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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Remote stereoinduction in the acylation of fully substituted enolates: tandem Reformatsky/quaternary Claisen condensations of silyl glyoxylates and β-lactones.

Greszler Stephen N SN Malinowski Justin T JT Johnson Jeffrey S JS

Journal of the American Chemical Society 20101118 49

Reformatsky reagents react sequentially with silyl glyoxylates and β-lactones to give highly functionalized Claisen condensation products. A heretofore undocumented instance of stereochemical 1,4-induction results in efficient transmission of β-lactone stereochemistry to the emerging fully substituted stereocenter. Second-stage transformations reveal that the five heteroatom-containing functionalities embedded within the products are entirely chemo-differentiated, a circumstance that permits rap ...[more]

PMID: 21087044

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