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Direct synthesis of aryl-annulated [c]carbazoles by gold(i)-catalysed cascade reaction of azide-diynes and arenes.

ABSTRACT: The gold-catalysed annulation of conjugated alkynes bearing an azido group with arenes gave annulated [c]carbazoles. Using benzene, pyrrole, and indole derivatives as the nucleophiles, benzo[c]-, pyrrolo[2,3-c]-, and indolo[2,3-c]carbazoles were produced, respectively. The reaction proceeded through pyrrole and benzene ring construction accompanied by the formation of two carbon-carbon and one carbon-nitrogen bond and the cleavage of two aromatic C-H bonds. The mechanism of the reaction with pyrrole was investigated by density functional theory calculations. N,N'-dimethylated indolo[2,3-c]carbazole showed dual ultraviolet-visible-near-infrared and fluorescence spectral changes upon electrolysis.

SUBMITTER: Kawada Y

PROVIDER: S-EPMC6244455 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Direct synthesis of aryl-annulated [c]carbazoles by gold(i)-catalysed cascade reaction of azide-diynes and arenes.

Kawada Yuiki Y Ohmura Shunsuke S Kobayashi Misaki M Nojo Wataru W Kondo Masaki M Matsuda Yuka Y Matsuoka Junpei J Inuki Shinsuke S Oishi Shinya S Wang Chao C Saito Tatsuo T Uchiyama Masanobu M Suzuki Takanori T Ohno Hiroaki H

Chemical science 20180910 44

The gold-catalysed annulation of conjugated alkynes bearing an azido group with arenes gave annulated [c]carbazoles. Using benzene, pyrrole, and indole derivatives as the nucleophiles, benzo[c]-, pyrrolo[2,3-c]-, and indolo[2,3-c]carbazoles were produced, respectively. The reaction proceeded through pyrrole and benzene ring construction accompanied by the formation of two carbon-carbon and one carbon-nitrogen bond and the cleavage of two aromatic C-H bonds. The mechan ...[more]

PMID: 30542591

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