Recyclable aluminium oxy-hydroxide supported Pd nanoparticles for selective hydrogenation of nitro compounds via sodium borohydride hydrolysis

Abstract

The reduction of aromatic/aliphatic nitro compounds to primary amines with high yields was easily realized by transfer hydrogenation comprising commercially available aluminium oxy-hydroxide-supported Pd nanoparticles (0.5 wt% Pd, Pd/AlO(OH)) as catalysts and NaBH₄ as the hydrogen reservoir at room temperature in a water/methanol mixture (v/v = 7/3). The presented catalytic methodology is highly efficient for the reduction of various nitro compounds as well as reusable. A variety of R-NO₂ derivatives were tested by performing the Pd/AlO(OH) catalysed reduction reaction and all the nitro compounds were selectively reduced to their corresponding primary amines in reaction times ranging from 0.75 to 13 min with yields reaching up to 99%. This process can be assessed as an eco-friendly method involving both reusable catalysts (Pd/AlO(OH) NPs) and hydrogen sources (NaBH₄).