Abstract

A green protocol for reduction of aromatic nitro compounds to amines with NaBH4/Cu(dmg)2 system in water as a green solvent

Author(s): Behzad Zeynizadeh, Saviz Zarrin, Shahriar Ashuri

Aromatic amines are important starting materials and intermediates for manufacturing a great variety of chemicals, such as dyestuffs, pharmaceutical products, agricultural chemicals, photo graphic chemicals, surfactants, textile auxiliaries, chelating agents and polymers. They are generally synthesized by reduction of nitro arenes. Aromatic amines can be prepared by a great variety of reduction methods. Probably the oldest industrially applied method is the reduction of nitrobenzenes with metal (usually iron, but also tin, zinc and aluminum can be employed) and water in the presence of small amounts of acid, first described by Bechamp in 1854. NaBH4 in the presence of catalytic amounts of copper dimethylglyoxime reduces various aromatic nitro compounds to the corresponding amines in high to excellent yields. Reduction reactions were carried out in water as a green solvent within immediate–35 minute at room temperature or under reflux conditions.