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Palladium impregnated amine co-condensed hexagonal mesoporous silicas (HMSÀ X) were synthesized (sol-gel process) using different amines (Ethylene diamine and pyridine) of various concentrations (0.25 equiv. and 2 equiv.). The effect of amine concentration on the local structure of hexagonal mesoporous silica was studied. The catalyst shows excellent catalytic activity and high TOF towards both Suzuki and Heck coupling reactions without using any base in reaction medium with the solvent DMF:water in (1:1) ratio. The catalyst was reused and it was recyclable up to three cycle without any appreciable loss of activity and the kinetics of the reaction varying different parameters also have been studied thoroughly.[a] P.

Liquid phase oxidation of styrene was performed over a series of indium impregnated mesoporous silica materials In-KIT-6, In-HMS-X and In-TUD-1of different morphologies with a constant indium loading of 1 wt % using molecular oxygen as an oxidant. Among these catalysts, In-HMS-X showed superior catalytic activity in terms of styrene conversion of 57 % and In-TUD-1 in terms of styrene oxide selectivity of 90 %. Larger surface area, larger pore diameter, more surface hydrophobicity, more surface acidity were found to be the deciding factors for better conversion. More oxygen uptake, higher reducibility of In species and well dispersion of metal over support were found to be the key enablers for better selectivity. All the catalysts were recyclable up to 5 th cycle.

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