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Updated: Oct 26, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Carbon Quaternization at the α-Position of Thiazoles: Iron-Catalyzed Hydroheteroarylation Using Unactivated Alkenes
Jinwoo Lee1, Chaeryn Jeong1, Hyungwoo Choi1
1Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul08826, Republic of Korea.
Abstract:
Thiazoles are privileged N-heterocyclic scaffolds ubiquitous in FDA-approved drugs, yet their clinical utility can be compromised by oxidative metabolism at the heterobenzylic position. Inspired by the metabolic-blocking strategy used in dabrafenib development, herein we report an iron-catalyzed strategy for direct α-quaternization of (benzo)thiazoles using unactivated alkenes. Under the proposed pathway, alkene-derived carbon-centered radicals undergo regioselective C2 addition and oxidative rearomatization, providing α-quaternary products without heteroarene preactivation or stoichiometric Lewis acids, thereby enabling analogue diversification.
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