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Complex fragment coupling by crotylation: A powerful tool for polyketide natural product synthesis.

ABSTRACT: The first examples of the use of crotylation as a stereocontrolled complex fragment coupling strategy are described. Asymmetric aldehyde isoprenylation provides access to 2-substituted-1,3-butadienes that may be subjected to highly regio- and stereoselective 1,4 hydrosilylation with trichlorosilane. After complexation with a chiral diamine, the 2-sub-stituted-cis-crotylsilanes may be employed in highly diastereoselective Sc(OTf)3-catalyzed aldehdye crotylation reactions.

SUBMITTER: Reznik SK

PROVIDER: S-EPMC4142647 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Complex fragment coupling by crotylation: A powerful tool for polyketide natural product synthesis.

Reznik Samuel K SK Marcus Brian S BS Leighton James L JL

Chemical science 20121101 11

The first examples of the use of crotylation as a stereocontrolled complex fragment coupling strategy are described. Asymmetric aldehyde isoprenylation provides access to 2-substituted-1,3-butadienes that may be subjected to highly regio- and stereoselective 1,4 hydrosilylation with trichlorosilane. After complexation with a chiral diamine, the 2-sub-stituted-<i>cis</i>-crotylsilanes may be employed in highly diastereoselective Sc(OTf)<sub>3</sub>-catalyzed aldehdye crotylation reactions. ...[more]

PMID: 25165502

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