Aryne Reactions of Polyhalobenzenes with Alkenyl and Alkynyl Grignard Reagents

Article abstract of DOI:10.1021/jo00228a030

Polyhalobenzenes react with alkenyl Grignard reagents to form from one to four new aryl-alkenyl bonds, depending on the particular polyhalobenzene used, in a single operation.Three types of reactions are involved in the mechanism: organometallic exchange, followed by one or more sequences of aryne formation, and nucleophilic addition to the aryne.Similar reactions can be accomplished with alkynyl Grignard reagents by using an alkyl Grignard reagent to initiate the exchange step.