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Gold-catalyzed highly regioselective oxidation of C-C triple bonds without acid additives: propargyl moieties as masked ?,?-unsaturated carbonyls.

ABSTRACT: Gold-catalyzed intermolecular oxidations of internal alkynes have been achieved with high regioselectivities using 8-alkylquinoline N-oxides as oxidants and in the absence of acid additives. Synthetically versatile ?,?-unsaturated carbonyls are obtained in good to excellent yields and with excellent E-selectivities. A range of functional groups such as THP, MOMO, N(3), OTBS, and N-Boc are tolerated. This reaction allows ?,?-unsaturated carbonyls to be masked as propargyl moieties, thus offering a practical solution to compatibility issues with these functional groups likely encountered in syntheses of complex structures.

SUBMITTER: Lu B

PROVIDER: S-EPMC2978523 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Gold-catalyzed highly regioselective oxidation of C-C triple bonds without acid additives: propargyl moieties as masked α,β-unsaturated carbonyls.

Lu Biao B Li Chaoqun C Zhang Liming L

Journal of the American Chemical Society 20101001 40

Gold-catalyzed intermolecular oxidations of internal alkynes have been achieved with high regioselectivities using 8-alkylquinoline N-oxides as oxidants and in the absence of acid additives. Synthetically versatile α,β-unsaturated carbonyls are obtained in good to excellent yields and with excellent E-selectivities. A range of functional groups such as THP, MOMO, N(3), OTBS, and N-Boc are tolerated. This reaction allows α,β-unsaturated carbonyls to be masked as propargyl moieties, thus offering ...[more]

PMID: 20853846

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