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Efficient route to 4H-1,3-oxazines through ring expansion of isoxazoles by rhodium carbenoids.

ABSTRACT: Studies related to the total synthesis of elisabethin C led to the discovery of a rhodium-catalyzed cascade sequence involving isoxazole ring expansion and a [4 + 3] cycloaddition. The scope of the isoxazole ring expansion was explored, resulting in the synthesis of a range of 4H-1,3-oxazines in 47-96% yield.

SUBMITTER: Manning JR

PROVIDER: S-EPMC2587331 | biostudies-literature | 2008 Jan

REPOSITORIES: biostudies-literature

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Efficient route to 4H-1,3-oxazines through ring expansion of isoxazoles by rhodium carbenoids.

Manning James R JR Davies Huw M L HM

Tetrahedron 20080101 29

Studies related to the total synthesis of elisabethin C led to the discovery of a rhodium-catalyzed cascade sequence involving isoxazole ring expansion and a [4 + 3] cycloaddition. The scope of the isoxazole ring expansion was explored, resulting in the synthesis of a range of 4H-1,3-oxazines in 47-96% yield. ...[more]

PMID: 19148263

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