A new encapsulated material [NiL2-SiO2] was prepared by direct sol-gel method. The material was characterized by fourier-transform (FTIR), proton nuclear magnetic resonance (1H NMR), ultraviolet-visible (UV-Vis), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) methods. The characterization results reveal that Ni-complex was highly dispersed into silica matrix and its structure remained intact after formation of the material. The material was found to be highly active and reusable for selective oxidation of primary and secondary alcohols. Under the optimal reaction conditions, primary and secondary alcohols were prevailingly oxidized to their corresponding acids or ketones. Moderate and efficient oxidation of primary and secondary alcohols with hydrogen peroxide catalyzed by NiL2, [bis(N-(2-hydroxyethyl)-2-(thiophene-2-ylmethylene) hydrazinecarbothioamido) nickel(II)], supported on mesoporous [NiL2-SiO2], at room temperature were reported.

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