Chemoselective reduction of a nitro group through transfer hydrogenation catalysed by Ru0-nanoparticles stabilized on modified Montmorillonite clay

Ru 0 -nanoparticles of approximately 5 nm size were generated by incipient impregnation of RuCl 3 into the nanopores of the acid activated Montmorillonite clay followed by polyol reduction. Acid activation of the clay increases the surface area by generating nanopores (010 nm), which act as a host and stabilize nanoparticles in the pores. The generated Ru 0 -nanoparticles exhibit inter-planar lattice fringe spacing of 0.21 nm of the face centered cubic lattice of Ru 0 crystals, and show efficient catalytic activity in the chemoselective transfer hydrogenation reduction of substituted nitrobenzenes to corresponding anilines with high yield of conversion (5697%) and selectivity (91100%) depending upon the nature of the substituents. The reactions were carried out in the presence of isopropanol, which served as the solvent as well as the reductant. The catalysts were found to be active for several catalytic runs. Generation of Ru 0 -nanoparticles into the nanopores of modified Montmorillonite and their catalytic activities in chemoselective transfer hydrogenation of the nitro group of various substituted nitrobenzenes under mild reaction conditions.