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Fischer carbene catalysis of alkynol cycloisomerization: application to the synthesis of the altromycin B disaccharide.

ABSTRACT: [reaction: see text] The tungsten-catalyzed cycloisomerization of alkynyl alcohols can be conducted without using photochemistry, using a stable tungsten Fischer carbene as the precatalyst for this transformation. A variety of alkynyl alcohols undergo cycloisomerization under these conditions to provide endocyclic enol ethers of five-, six-, and seven-membered ring sizes. The utility of this method is further demonstrated in the stereoselective synthesis of the disaccharide substructure of altromycin B.

SUBMITTER: Koo B

PROVIDER: S-EPMC4604442 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature

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Fischer carbene catalysis of alkynol cycloisomerization: application to the synthesis of the altromycin B disaccharide.

Koo Bonsuk B McDonald Frank E FE

Organic letters 20070327 9

[reaction: see text] The tungsten-catalyzed cycloisomerization of alkynyl alcohols can be conducted without using photochemistry, using a stable tungsten Fischer carbene as the precatalyst for this transformation. A variety of alkynyl alcohols undergo cycloisomerization under these conditions to provide endocyclic enol ethers of five-, six-, and seven-membered ring sizes. The utility of this method is further demonstrated in the stereoselective synthesis of the disaccharide substructure of altro ...[more]

PMID: 17385878

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