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Access to dienophilic ene-triketone synthons by oxidation of diketones with an oxoammonium salt.

ABSTRACT: Here we describe the oxidation of 1,3-cyclohexanediones with 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (Bobbitt's salt) to generate 5-ene-1,2,4-triones in moderate-to-good (40-80%) yields. This inexpensive oxidant facilitated an unprecedented cascade of oxidation and elimination to yield novel ene-triketones. The reactivity of these products was explored in the Diels-Alder reaction and provided moderate-to-good yields of cycloaddition products. The products described in this study represent unique, densely functionalized, and versatile building blocks for the synthesis of more complex molecules.

SUBMITTER: Eddy NA

PROVIDER: S-EPMC3459679 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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Access to dienophilic ene-triketone synthons by oxidation of diketones with an oxoammonium salt.

Eddy Nicholas A NA Kelly Christopher B CB Mercadante Michael A MA Leadbeater Nicholas E NE Fenteany Gabriel G Fenteany Gabriel G

Organic letters 20111229 2

Here we describe the oxidation of 1,3-cyclohexanediones with 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (Bobbitt's salt) to generate 5-ene-1,2,4-triones in moderate-to-good (40-80%) yields. This inexpensive oxidant facilitated an unprecedented cascade of oxidation and elimination to yield novel ene-triketones. The reactivity of these products was explored in the Diels-Alder reaction and provided moderate-to-good yields of cycloaddition products. The products descri ...[more]

PMID: 22206582

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