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A stable enol from a 6-substituted benzanthrone and its unexpected behaviour under acidic conditions.

ABSTRACT: Treatment of benzanthrone (1) with biphenyl-2-yl lithium leads to the surprisingly stable enol 4, which is converted by dehydrogenation into the benzanthrone derivative 7. Under acidic conditions 4 isomerises to the spiro compound 11 and the bicyclo[4.3.1]decane derivative 12. Furthermore, the formation of 7 and the hydrogenated compound 13 is observed. A mechanism for the formation of the reaction products is proposed and supported by DFT calculations.

SUBMITTER: Debeaux M

PROVIDER: S-EPMC2707016 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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A stable enol from a 6-substituted benzanthrone and its unexpected behaviour under acidic conditions.

Debeaux Marc M Brandhorst Kai K Jones Peter G PG Hopf Henning H Grunenberg Jörg J Kowalsky Wolfgang W Johannes Hans-Hermann HH

Beilstein journal of organic chemistry 20090616

Treatment of benzanthrone (1) with biphenyl-2-yl lithium leads to the surprisingly stable enol 4, which is converted by dehydrogenation into the benzanthrone derivative 7. Under acidic conditions 4 isomerises to the spiro compound 11 and the bicyclo[4.3.1]decane derivative 12. Furthermore, the formation of 7 and the hydrogenated compound 13 is observed. A mechanism for the formation of the reaction products is proposed and supported by DFT calculations. ...[more]

PMID: 19597557

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A stable enol from a 6-substituted benzanthrone and its unexpected behaviour under acidic conditions.

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A stable enol from a 6-substituted benzanthrone and its unexpected behaviour under acidic conditions.

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