A novel approach for the synthesis of “Spirooxindoles” by using γ-Al2O3 coated cordierite monolith honeycomb reinforced with Ti0.97Pd0.03O2−δ Catalyst

M.P. Manasa, Keshav Kumar Harish, G.O.Obaiah, Mahendra Madegowda, M.Umashankara, P.G.Chndrashekara

The present work was mainly focused on an enhancement of γ-Al2O3 coated cordierite monolith honeycomb reinforced Ti0.97 Pd0.03 O2 catalyst to achieve selective high rates in the C-N coupling reaction. The synthesis of Ti0.97Pd0.03O2 catalyst was prepared using Titanium isopropoxide {Ti (OC3H7)4}, Pdcl2 and Glycine precursors. In typical coating of (3 % atom Pd on TiO2), 9.7 mmol of TiO(NO3)2 solution, 0.3 mmol PdCl2 and 10 mmol glycine were dissolved to make a solution. The obtained sample of the monolith before and after coating and catalytic activity was studied by using PXRD, IR, Mass spectroscopy, TEM and SEM. The surface image of the catalyst coated monolith was characterized by FEI Quanta scanning electron microscope. The potential use of the catalyst  for organic synthesis and in the industrial passive autocatalytic recombines (PAR) was examined for the formation of spirocyclic compound (M3) which is illustrated in scheme 1. In our study we found that the vinlyoxime (M2) prepared by precursor compound (M1) in the presence of catalyst undergo aryl group migration from sp2 carbon atom to oxime N-atom and from nitrone intermediate (M*) which undergo subsequent inter molecular cyclization and yield spiro compound (M3).