Nitroarenes were chemoselectively reduced to the corresponding amines using zinc and aqueous ammonium salts in ionic liquids as a safe and recyclable reaction medium. Our results specify the effect of ammonium salts in the process; the combination of Zn/NH4Cl in [bmim][PF6] or Zn/HCO2NH4 in [bmim][BF4] were the suitable conditions for the reduction of nitroarenes. Azobenzenes were also smoothly reduced to hydrazobenzenes with Zn/HCO2NH4 (aq.) in recyclable [bmim][BF4] without any over reduction to the corresponding anilines.
Bibliographical noteFunding Information:
We thank the Department of Science and Technology (DST), the Council of Scientific and Industrial Research (CSIR), New Delhi for financial assistance. J.D., R.K.G. and C.S. thank CSIR, U.G.C. for fellowships.
- Azo compounds
- Ionic liquids