Iodine-Catalyzed Annulation Reaction of Ortho-Formylarylketones with Indoles: A General Strategy for the Synthesis of Indolylbenzo[ b]carbazoles

Sundaram Suresh; Veerababurao Kavala; Ching-Fa Yao

doi:10.1021/acs.joc.2c02868

Iodine-Catalyzed Annulation Reaction of Ortho-Formylarylketones with Indoles: A General Strategy for the Synthesis of Indolylbenzo[ b]carbazoles

J Org Chem. 2023 Mar 17;88(6):3666-3677. doi: 10.1021/acs.joc.2c02868. Epub 2023 Mar 8.

Authors

Sundaram Suresh¹, Veerababurao Kavala¹, Ching-Fa Yao¹

Affiliation

¹ Department of Chemistry, National Taiwan Normal University, No. 88, Sec. 4, Ting-Zhou Road, Taipei 11677, Taiwan, Taiwan, R.O.C.

PMID: 36890622
DOI: 10.1021/acs.joc.2c02868

Abstract

The iodine-catalyzed cascade reaction of ortho-formylarylketones with indoles for the synthesis of indolylbenzo[b]carbazoles is reported. The reaction is initiated in the presence of iodine by two successive nucleophilic additions of indoles with an aldehyde group of ortho-formylarylketones, and the ketone does not undergo a nucleophilic addition and only involves in the Friedel-Crafts-type cyclization. A variety of substrates are tested, and the efficiency of this reaction is demonstrated with gram-scale reactions.