STEREOCONTROLLED SYNTHESIS OF CYCLIC ETHERS BY INTRAMOLECULAR HETERO-MICHAEL ADDITION .4. ENANTIOMERIC SYNTHESIS OF SUBSTITUTED AND FUSED OXEPANES

Citation
Ma. Soler et al., STEREOCONTROLLED SYNTHESIS OF CYCLIC ETHERS BY INTRAMOLECULAR HETERO-MICHAEL ADDITION .4. ENANTIOMERIC SYNTHESIS OF SUBSTITUTED AND FUSED OXEPANES, Tetrahedron letters, 34(34), 1993, pp. 5471-5474
Citations number
20
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
ISSN journal
00404039
Volume
34
Issue
34
Year of publication
1993
Pages
5471 - 5474
Database
ISI
SICI code
0040-4039(1993)34:34<5471:SSOCEB>2.0.ZU;2-S
Abstract
The use of an intramolecular hetero-Michael addition of enantiomerical ly enriched 7-alkoxy4-benzoyloxy-2,3-unsaturated esters for the synthe sis of endo-substituted oxepanes is described, The stereochemistry in the cyclization step is governed by the geometry of the double bond in the unsaturated ester and the presence of a Z-double bond in the line ar chain is required in order to achieve good yields. The synthesis of the fused oxepane-tetrahydropyran nucleus of marine polyether toxins with absolute control of all the stereocentres is described.