Work

Overcoming O–H Insertion to Para-Selective C–H Functionalization of Free Phenols: Rh(II)/Xantphos Catalyzed Geminal Difunctionalization of Diazo Compounds

Year: 2022

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Para -selective C–H functionalization of free phenols by metal carbenoids is rather challenging due to the generally more favorable competing O–H insertion. Herein, with the use of the combination of Rh(II) and a Xantphos ligand as the catalyst, a novel multicomponent reaction of free phenols, diazoesters, and allylic carbonates was successfully developed, affording a wide variety of phenol derivatives, bearing an all-carbon quaternary center and a synthetically useful allylic unit. This reaction is likely to occur through a tandem process of carbene-induced para -selective C–H functionalization, followed by Rh(II)/Xantphos-catalyzed allylation. The distinctive reactivity of para -selective C–H rather than O–H insertion for the carbenoid intermediate, combined with features of excellent functional group compatibility, high atom and step economy, and ease in further diversification of the products, might render this protocol highly attractive in facile functionalization of unprotected phenols.

Source: ACS Central Science

DOI: 10.1021/acscentsci.2c00004

Authors: Yang Yang, Bin Lu, Guiqing Xu, Xiaoming Wang

Institutions: Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, State Key Laboratory of Organometallic Chemistry, Henan Normal University

Language: English

Topic: Cyclopropane Reaction Mechanisms

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: diamond

Funder: National Natural Science Foundation of China

Award: G387334713