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Tandem dinucleophilic cyclization of cyclohexane-1,3-diones with pyridinium salts.

ABSTRACT: The cyclization of cyclohexane-1,3-diones with various substituted pyridinium salts afforded functionalized 8-oxa-10-aza-tricyclo[7.3.1.0(2,7)]trideca-2(7),11-dienes. The reaction proceeds by regioselective attack of the central carbon atom of the 1,3-dicarbonyl unit to 4-position of the pyridinium salt and subsequent cyclization by base-assisted proton migration and nucleophilic addition of the oxygen atom to the 2-position, as was elucidated by DFT computations. Fairly extensive screening of bases and additives revealed that the presence of potassium cations is essential for formation of the product.

SUBMITTER: Kiamehr M

PROVIDER: S-EPMC3701411 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Tandem dinucleophilic cyclization of cyclohexane-1,3-diones with pyridinium salts.

Kiamehr Mostafa M Moghaddam Firouz Matloubi FM Mkrtchyan Satenik S Semeniuchenko Volodymyr V Supe Linda L Villinger Alexander A Langer Peter P Iaroshenko Viktor O VO

Beilstein journal of organic chemistry 20130610

The cyclization of cyclohexane-1,3-diones with various substituted pyridinium salts afforded functionalized 8-oxa-10-aza-tricyclo[7.3.1.0(2,7)]trideca-2(7),11-dienes. The reaction proceeds by regioselective attack of the central carbon atom of the 1,3-dicarbonyl unit to 4-position of the pyridinium salt and subsequent cyclization by base-assisted proton migration and nucleophilic addition of the oxygen atom to the 2-position, as was elucidated by DFT computations. Fairly extensive screening of b ...[more]

PMID: 23843903

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