Synthesis, characterization and catalytic oxidation of cyclohexene with molecular oxygen over host (nanopores of zeolite-Y)/guest ([Ni([R]2-N2X2)]2+ (R = H, CH3; X = NH, O, S) nanocatalyst

Abstract

Nickel(II) complexes of 12-membered macrocyclic ligands with different donating atoms (N2O2, N2S2 and N4) in the macrocyclic ring have been encapsulated in the nanocavity of zeolite-Y by the fexible-ligand method. Nickel(II) complexes with macrocyclic ligands were entrapped in the nanocavity of zeolite-Y by a two-step process in the liquid phase: (i) adsorption of precursor ligand; 1,2-di(o-aminophenyl-, amino, oxo, thio)ethane, N2X2; in the supercages of the Ni(II)–NaY, and (ii) in situ condensation of the Ni(II) precursor complex; [Ni(N2X2)]2+; with glyoxal or biacetyl. The new host–guest nanocatalysts (HGNM), [Ni([R]2-N2X2)]2+–NaY (R = H, CH3; X = NH, O, S), have been characterized by FT-IR, DRS and UV–Vis spectroscopic techniques, XRD and elemental analysis, as well as nitrogen adsorption, and were used for oxidation of cyclohexene with molecular oxygen.