Pyridinium Dichlorobromate: A New Stable Brominating Agent for Aromatic Compounds

Abstract

Pyridinium dichlorobromate (PyHBrCl₂, 1) is a new example of iminium-trihalide complexes. The compound is prepared from pyridine and chlorine in the presence of aqueous hydrogen bromide. The crystalline trihalide is quite stable and acts as a safe source of positive bromine. It shows a remarkable reactivity towards aromatic compounds compared with other bromine complexes. It is also considered as a potential source for bromine chloride BrCl.

Key words

pyridinium dichlorobromate - bromination - bromine chloride - aromatic compounds

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