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Organocatalytic asymmetric addition of malonates to unsaturated 1,4-diketones.

ABSTRACT: The organocatalytic Michael addition of malonates to symmetric unsaturated 1,4-diketones catalyzed by thiourea and squaramide derivatives with Cinchona alkaloids afforded the formation of a new C-C bond in high yields (up to 98%) and enantiomeric purities (up to 93%). The absolute configuration of the product was suggested from comparison of the experimental and calculated VCD spectra of the reaction product 3a.

SUBMITTER: Zari S

PROVIDER: S-EPMC3458770 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Organocatalytic asymmetric addition of malonates to unsaturated 1,4-diketones.

Zari Sergei S Kailas Tiiu T Kudrjashova Marina M Oeren Mario M Järving Ivar I Tamm Toomas T Lopp Margus M Kanger Tõnis T

Beilstein journal of organic chemistry 20120904

The organocatalytic Michael addition of malonates to symmetric unsaturated 1,4-diketones catalyzed by thiourea and squaramide derivatives with Cinchona alkaloids afforded the formation of a new C-C bond in high yields (up to 98%) and enantiomeric purities (up to 93%). The absolute configuration of the product was suggested from comparison of the experimental and calculated VCD spectra of the reaction product 3a. ...[more]

PMID: 23019480

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