Preparation of a novel acidic functionalized diatomite and its catalytic application in the synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives

Diatomite has been functionalized using 3-chloropropyl trimethoxysilane, hexamethylenetetramine, and chlorosulfonic acid to create Diatomie@Hexamethylenetetramine-SO3H (Diatomie@HMTA-SO3H) and characterized with EDS, TGA, XRD, SEM, and FT-IR methods. This novel heterogeneous catalyst was used for the synthesis of 2,3-dihydroquinazolinone derivatives under solvent-free conditions using isatoic anhydride, different aldehydes, and ammonium acetate. The antibacterial activity of the synthesized compounds against two microorganisms, including a Gram-positive Staphylococcus aureus and a Gram-negative Pseudomonas Aeruginosa, was investigated by the Kirby-Bayer method. This method has several benefits, including high product purity and yield, short reaction times, simple work-up and purification procedures, and employing an environmentally friendly, affordable, recoverable, and reusable catalyst.