Reduction of nitroarenes to azoxybenzenes by potassium borohydride in water
Yufang Liu1, Bo Liu, Ailing Guo
1School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China.
Abstract:
The synthesis of the azoxybenzenes by the reduction of nitroarenes with reducing agent potassium borohydride in water was reported for the first time. PEG-400 was used as a phase transfer catalyst and could effectively catalyze the reduction. The electronic effects of substituent groups play an important role in determining the reduction efficiencies. Electron-withdrawing substituents promote the formation of the azoxybenzene products, while electron-releasing groups retard the reductions to various degrees depending on the extent of their electron-donating ability.
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