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Diastereoselective Prins-type reaction of cycloalkenylcyclopropanol silyl ethers and alpha,beta-unsaturated aldehyde acetals.

ABSTRACT: Electrophilic addition of 1-(1-cyclohexenyl)-1-cyclopropanol trimethylsilyl ether to alpha,beta-unsaturated aldehyde acetals under Lewis acidic conditions proceeds with good to excellent diastereoselectivity to afford spirocyclobutanones containing three contiguous stereocenters. A convenient entry to enantioselective syntheses is available by use of a nonracemic C2-symmetric acetal. Elaboration of the resulting adducts provides ready access to medium-sized carbocycles.

SUBMITTER: Lysenko IL

PROVIDER: S-EPMC2597285 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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Diastereoselective Prins-type reaction of cycloalkenylcyclopropanol silyl ethers and alpha,beta-unsaturated aldehyde acetals.

Lysenko Ivan L IL Oh Heong-Sub HS Cha Jin Kun JK

The Journal of organic chemistry 20070913 21

Electrophilic addition of 1-(1-cyclohexenyl)-1-cyclopropanol trimethylsilyl ether to alpha,beta-unsaturated aldehyde acetals under Lewis acidic conditions proceeds with good to excellent diastereoselectivity to afford spirocyclobutanones containing three contiguous stereocenters. A convenient entry to enantioselective syntheses is available by use of a nonracemic C2-symmetric acetal. Elaboration of the resulting adducts provides ready access to medium-sized carbocycles. ...[more]

PMID: 17850161

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