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Carbonyl-assisted reverse regioselective cascade annulation of 2-acetylenic ketones triggered by Ru-catalyzed C-H activation.

ABSTRACT: The first reverse regioselective intermolecular annulation of aryl substituted 2-acetylenic ketones with O-substituted N-hydroxybenzamides or acrylamides followed by tandem cyclization via ruthenium-catalyzed C-H activation, is reported. Excellent reverse selectivity of alkyne insertion was induced by the weak coordination between the carbonyl group and ruthenium complex. This highly efficient and practical reaction has a broad range of substrate scope with excellent functional-group tolerance. The tandem reaction provides a wide range of polycyclic products that have an indozilidine structural motif, and are found to potentially be synthetically and pharmaceutically valuable.

SUBMITTER: Gollapelli KK

PROVIDER: S-EPMC6016575 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Carbonyl-assisted reverse regioselective cascade annulation of 2-acetylenic ketones triggered by Ru-catalyzed C-H activation.

Gollapelli Krishna Kumar KK Kallepu Shivakrishna S Govindappa Nagendra N Nanubolu Jagadeesh Babu JB Chegondi Rambabu R

Chemical science 20160412 7

The first reverse regioselective intermolecular annulation of aryl substituted 2-acetylenic ketones with O-substituted N-hydroxybenzamides or acrylamides followed by tandem cyclization via ruthenium-catalyzed C-H activation, is reported. Excellent reverse selectivity of alkyne insertion was induced by the weak coordination between the carbonyl group and ruthenium complex. This highly efficient and practical reaction has a broad range of substrate scope with excellent functio ...[more]

PMID: 30155126

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