A General Method for the Dibromination of Vicinal sp C-H Bonds Exploiting Weak Solvent-Substrate Noncovalent Interactions.

Org Lett

State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, P. R. China.

Published: April 2021

A general procedure of 1,2-dibromination of vicinal sp C-H bonds of arylethanes using -bromosuccinimide as the bromide reagent without an external initiator has been established. The modulation of the strength of the intermolecular noncovalent interactions between the solvent and arylethane ethanes, quantitatively evaluated via quantum chemical calculations, allows us to circumvent the fact that arylethane ethane cannot be dibrominated through traditional methods. The mechanism was explored by both experiments and quantum chemical calculations, revealing a radical chain with HAA process.

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http://dx.doi.org/10.1021/acs.orglett.0c04235DOI Listing

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