Systematic Studies of Functional Group Tolerance and Chemoselectivity in Carbene-Mediated Intramolecular Cyclopropanation and Intermolecular C–H Functionalization

Abstract

Generating reliable data on functional group compatibility and chemoselectivity is essential for evaluating the practicality of chemical reactions and predicting retrosynthetic routes. In this context, we performed systematic studies using a functional group evaluation kit including 26 kinds of additives to assess the functional group tolerance of carbene-mediated reactions. Our findings revealed that some intermolecular heteroatom–hydrogen insertion reactions proceed faster than intramolecular cyclopropanation reactions. Lewis basic functionalities inhibited rhodium-catalyzed C–H functionalization of indoles. While performing these studies, we observed an unexpected C–H functionalization of a 1-naphthol variant used as an additive.