Oxidative Homocoupling of Aryl, Alkenyl, and Alkynyl Grignard Reagents with TEMPO and Dioxygen

Abstract

Without a transition metal, unsaturated organomagnesium compounds undergo homocoupling in the presence of a substoichiometric amount of the oxidant 2,2,6,6-tertramethylpiperidine-N-oxyl radical (TEMPO) and oxygen. Alkynyl Grignard reagents can even be coupled to give the corresponding diynes with dioxygen in the absence of a catalyst (see scheme). Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.