Construction of contiguous quaternary carbon centers enabled by dearomatization of phenols with 3-bromooxindoles.

Org Biomol Chem

Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, 22 Xinong Road, Yangling, 712100, Shaanxi, China.

Published: October 2024

A transition metal-free and oxidation-free dearomatization of phenols through conjugate addition to generated indol-2-one from 3-bromooxindole is detailed in this report. This methodology offers an effective approach for the synthesis of a range of 3-substituted oxindoles containing contiguous quaternary carbon centers (CQCCs) with yields of up to 99%. The reaction is characterized by mild conditions, exceptional efficiency, environmental compatibility, favorable functional group tolerance, and scalability to large-scale production.

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http://dx.doi.org/10.1039/d4ob01163eDOI Listing

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