Condensation of Active Methylene and Substituted Aldehydes over Mesoporous Nickel Oxides Nanostructures: A Combined Experimental and DFT Study

摘要

Mesoporous NiO nanoarchitectures (NAs) with controlled hexagonal platelet- and flower-like morphology were synthesized using facile hydrothermal methods in different reaction conditions. The NiO NAs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), N-2 adsorption /desorption isotherms, and wide-angle X-ray diffraction. It was found that controlled morphology, large surface areas, and high crystallinity of NiO NAs offered high catalytic reactivity toward Knoevenagel condensation reactions. Large reaction yields in an aqueous media and easy separation of the NiO NAs without losing the catalytic activity were observed. Further, the formation mechanism of -C=C- bonds over NiO NAs surface was explored by density functional theory (DFT). These findings open a new avenue for efficient -C=C- bonds formation using reusable NiO NAs catalyst without using any expensive solvents.