Anchoring of Cu-dimethylglyoxime complex in MCM-41 matrix: a new, recyclable, and highly efficient nanocatalyst for the green preparation of 2,3-dihydroquinazolin-4(1H)-ones

A new heterogeneous nanocatalyst containing Cu-dimethylglyoxime complex grafted to an MCM-41 matrix was synthesized. This recoverable nanocomposite was applied as a highly effective, green, thermally stable catalyst in the one-pot reductive cyclization of aromatic aldehydes with 2-aminobenzamide. 2,3-Dihydroquinazolin-4(1H)-ones were obtained in 80-98% yield. The MCM-41-silylcyclopropyl-dimethylglyoxime-Cu heterogeneous nanocomposite was well identified using X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, Brunauer-Emmett-Teller technique, and thermogravimetric analysis. The eco-friendly nanocatalyst demonstrated excellent recyclability: it could be reused for at least six successive cycles without any notable decrease in its catalytic function. [GRAPHICS] .