Tandem β-fragmentation-intramolecular functionalization of alkoxyradicals. An approach to the synthesis of a and a'rings of limonin

doi:10.1016/S0040-4039(00)95892-1

Tetrahedron Letters

Volume 28, Issue 9, 1987, Pages 981-984

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Abstract

A tandem β-fragmentation-intramolecular functionalization reaction is observed by photolysis of steroidal lactols in the presence of several oxidation agents under oxygen. An application of this reaction to the synthesis of A and A'rings of limonin (1) is described.

Photolysis of the steroidal lactol (1), in the presence of several oxidation agents under oxygen, led to compound (2) by the title reaction. Under argon the lactone (3) was formed instead.

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Tandem β-fragmentation-intramolecular functionalization of alkoxyradicals. An approach to the synthesis of a and a'rings of limonin

Abstract

J. Am. Chem. Soc.

J. Chem. Soc.

Fortschritte der Chemie Organischer Naturstoffe

Helv. Chim. Acta

Helv. Chim. Acta

Helv. Chim. Acta

Tetrahedron Letters