Bromination of Arenes Using I₂O₅-KBr in Water

Abstract

An efficient and environmentally benign bromination of various aromatic compounds using aN aqueous I₂O₅-KBr system at room temperature has been developed in this work. A series of aromatic compounds such as acetophenones, benzaldehydes, benzoic acids, anilines, amides, and aminopyridine have been successfully brominated in excellent regioselectivities and good yields under the typical reaction conditions. The features of KBr as brominating reagent, water as solvent, and mild conditions make this system an attractive synthetic procedure.

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GRAPHICAL ABSTRACT

Keywords:

• Arene
• bromination
• KBr

ACKNOWLEDGMENTS

This project is supported by the National Science Foundation of China (Nos. 21002045, 21272096) and the Fundamental Research Funds for the Central Universities (lzujbky-2012-55). We also thank the State Key Laboratory of Applied Organic Chemistry and Lanzhou University for financial support.

Notes

^a Reaction conditions: 4-methoxyacetophenone (0.5 mmol, 1 eq.), solvent (2 mL), stirred at room temperature for 10 h.

^b Isolated yield.

^a Reaction conditions: aromatic compound (0.5 mmol, 1 eq.), I₂O₅ (1.0 mmol, 2 eq.), KBr (1.25 mmol, 2.5 eq.), H₂O (2 mL), stirred at room temperature for the indicated time.

^b Isolated yield.