Synthesis of azine perhalide adducts

Abstract

Bromine reacts with para-substituted benzaldehyde azines in anhydrous acetic acid, to form substituted azinium perbromides (AzineH⁺ Br₃^–) in good yields. Chemical (positive bromine analysis, as well as the ability of the azinium perbromide to brominate aromatic nuclei), and physical (i.r. and n.m.r.), data support the structure we propose for these compounds. Tri-iodide ion also forms a similar compound with benzaldehyde azine in glacial acetic acid, whereas chlorine reacts with the azine to form a dichloromethine-substituted product.