Electrochemical Synthesis of Dimeric λ 3 -Bromane: Platform for Hypervalent Bromine(III) Compounds.

A straightforward and scalable approach to a previously unreported class of cyclic hypervalent Br(III) species capitalizes on the anodic oxidation of aryl bromide to dimeric benzbromoxole that serves as a versatile platform to access a range of structurally diverse Br(III) congeners such as acetoxy-, alkoxy-, and ethynyl-λ 3 -bromanes as well as diaryl-λ 3 -bromanes. The synthetic utility of dimeric λ 3 -bromane is exemplified by photoinduced Minisci-type heteroarylation reactions and benzylic oxidation.