Design and Synthesis of Indazole–Indole Hybrid via tert-Butyl Nitrite Mediated Cascade Diazotization/Isomerization/Cyclization

• DOI: 10.1021/acs.joc.4c00377
• Publication Date: 2024-04-25T16:01:22Z
• Authors: Abhishek Kar; Gopal Rana; Rajkamal Sahoo; Sourav Ghosh; Umasish Jana
• Keywords: Indazole

In this report, a tert-butyl nitrite (TBN)-mediated straightforward metal-free approach has been presented for the synthesis of diverse range C-3-substituted indazole–indole hybrids using readily accessible 2-(indolin-3-ylidenemethyl)aniline derivatives. This strategy is proposed to occur via diazonium salt intermediate that capable cascade isomerization and intramolecular C–N bond formation through 5-endo-dig cyclization achieve wide variety in good yields.