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Updated: Feb 23, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
A tandem annulation with a [1,3]-hydride transfer as the key step leading to isochromans
Yingwei Wang1, Guangxun Li, Hongxin Liu
1Department of Pharmaceutical & Biological Engineering, School of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China. gzhao@scu.edu.cn.
Abstract:
An unprecedented method that enables the direct coupling of an α-C-H bond in alcohols with 2-arylacetaldehydes through a [1,3]-hydride transfer ([1,3]-HT) of oxocarbenium ions catalyzed by a Lewis acid has been developed. The redox neutral preparation of the isochroman derivatives proceeds via a tandem condensation/[1,3]-HT/Friedel-Crafts sequence with moderate to good yields. Deuterium-labeling studies provide mechanistic insights and reveal that the redox functionalization proceeds via a [1,3]-HT.
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