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One-pot synthesis of highly functionalized pyridines via a rhodium carbenoid induced ring expansion of isoxazoles.

ABSTRACT: A concise one-pot synthesis of highly functionalized pyridines has been developed. The first step in the reaction sequence is the formal insertion of rhodium vinylcarbenoids across the N-O bond of isoxazoles. Upon heating, the insertion products undergo a rearrangement to give 1,4-dihydropyridines. DDQ oxidation then affords the corresponding pyridines in 31-84% yield. The process has proven general with a range of carbenoid and isoxazole components and represents a unique disconnection strategy for the synthesis of functionalized pyridines.

SUBMITTER: Manning JR

PROVIDER: S-EPMC2921945 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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One-pot synthesis of highly functionalized pyridines via a rhodium carbenoid induced ring expansion of isoxazoles.

Manning James R JR Davies Huw M L HM

Journal of the American Chemical Society 20080613 27

A concise one-pot synthesis of highly functionalized pyridines has been developed. The first step in the reaction sequence is the formal insertion of rhodium vinylcarbenoids across the N-O bond of isoxazoles. Upon heating, the insertion products undergo a rearrangement to give 1,4-dihydropyridines. DDQ oxidation then affords the corresponding pyridines in 31-84% yield. The process has proven general with a range of carbenoid and isoxazole components and represents a unique disconnection strategy ...[more]

PMID: 18549206

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