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Diastereoselective Organocatalytic Addition of ?-Angelica Lactone to ?-Halo-?-ketoesters.

ABSTRACT: A quinidine-catalyzed diastereoselective addition of ?-angelica lactone to ?-halo-?-ketoesters is reported. The ?-angelica lactone displays unusual regioselectivity in this reaction, acting as a nucleophile at the ?-position to provide fully substituted glycolic esters with three contiguous stereocenters. Subsequent diastereoselective hydrogenation provides an additional stereocenter within the lactone.

SUBMITTER: Griswold JA

PROVIDER: S-EPMC5324730 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Diastereoselective Organocatalytic Addition of α-Angelica Lactone to β-Halo-α-ketoesters.

Griswold Jessica A JA Horwitz Matthew A MA Leiva Leslie V LV Johnson Jeffrey S JS

The Journal of organic chemistry 20170206 4

A quinidine-catalyzed diastereoselective addition of α-angelica lactone to β-halo-α-ketoesters is reported. The α-angelica lactone displays unusual regioselectivity in this reaction, acting as a nucleophile at the α-position to provide fully substituted glycolic esters with three contiguous stereocenters. Subsequent diastereoselective hydrogenation provides an additional stereocenter within the lactone. ...[more]

PMID: 28164699

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