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The Cycloaddition of the Benzimidazolium Ylides with Alkynes: New Mechanistic Insights.

ABSTRACT: New insights concerning the reaction mechanism in the cycloaddition reaction of benzimidazolium ylides to activated alkynes are presented. The proposed pathway leading both to 2-(1H-pyrrol-1-yl)anilines and to pyrrolo[1,2-a]quinoxalin-4(5H)-ones involves an opening of the imidazole ring from the cycloaddition product, followed by a nucleophilic attack of the aminic nitrogen to a proximal carbonyl group and the elimination of a leaving group. The mechanistic considerations are fully supported by experimental data, including the XRD resolved structure of the key reaction intermediate.

SUBMITTER: Moldoveanu C

PROVIDER: S-EPMC4880325 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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The Cycloaddition of the Benzimidazolium Ylides with Alkynes: New Mechanistic Insights.

Moldoveanu Costel C Zbancioc Gheorghita G Mantu Dorina D Maftei Dan D Mangalagiu Ionel I

PloS one 20160525 5

New insights concerning the reaction mechanism in the cycloaddition reaction of benzimidazolium ylides to activated alkynes are presented. The proposed pathway leading both to 2-(1H-pyrrol-1-yl)anilines and to pyrrolo[1,2-a]quinoxalin-4(5H)-ones involves an opening of the imidazole ring from the cycloaddition product, followed by a nucleophilic attack of the aminic nitrogen to a proximal carbonyl group and the elimination of a leaving group. The mechanistic considerations are fully supported by ...[more]

PMID: 27224656

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