A hassle-free and cost-effective transfer hydrogenation strategy for the chemoselective reduction of arylnitriles to primary amines through in situ-generated nickelII dihydride intermediate in water

• Green reaction medium (use of water solvent). • High chemoselectivity. • Use of available materials for one of the important organic transformation. • Reduction (or hydrogenation) process has done via in situ -generated nickel II dihydride intermediate. • Ni 2 B-free trajectory. • Good-to-excellent yields of the desired products. • Relatively short reaction times. • Base- and ligand-free protocol. • Cost-effective and convenient synthetic protocol. • Easy work-up procedure. In this paper, we have introduced a new, simple, efficient, inexpensive, and chemoselective transfer hydrogenation strategy for the straightforward reduction of arylnitriles to corresponding primary amines using sodium borohydride (NaBH 4 ) and nickel acetate tetrahydrate (Ni(OAc) 2 •4H 2 O) through in situ -generated nickel II dihydride intermediate in the water medium at 50 ᵒ C. The presented methodology features moderate reaction conditions, nickel boride (Ni 2 B)-free trajectory, good-to-excellent yields of the products, relatively short reaction times, satisfactory chemoselectivity, and does not involve the use of toxic organic solvent and also any base or ligand.