Ultrasound assisted one pot synthesis of imidazole derivatives using diethyl bromophosphate as an oxidant

Abstract

A one pot, three-component condensation of benzoin/benzyl, an aldehyde, and ammonium acetate using diethyl bromophosphate as a mild oxidant is achieved to form trisubstituted imidazole compounds. Under ultrasound irradiation, a smooth condensation occurs to get the 2, 4, 5-triaryl-1H-imidazole compounds in good to excellent yields. The study explores the scope and limitation of diethyl bromophosphate as an oxidant and suggests advantages, viz., simplicity of operation, reduction in time, and an increase in product yields.

Ultrasound-promoted one-pot three component synthesis of tetrazoles catalyzed by zinc sulfide nanoparticles as a recyclable heterogeneous catalyst

“…These are ascribed to the shock wave and microjet manufactured by the cavitations. In term of sonication, dispersed ZnS nanoparticles in solution affords extra nucleation sites for acoustic cavity formation on its surface and gain the number of micro bubbles in the solution [32][33][34][35]. The quick implosion of these bubbles in the liquids generates localized hot spots with very short lifetimes.…”

Use of Ultrasound in the Synthesis of Heterocycles of Medicinal Interest

“…Nagargoje et al [62] described a one-pot, three-component condensation for the synthesis of trisubstituted imidazole compounds under ultrasound irradiation (Scheme 14). The starting materials were benzoin/benzyl (47), an SCHEME 10 Synthesis of 5-aryl-1,3-diphenylpyrazoles (34).…”

Ultrasonics Promoted Synthesis of 5-(Pyrazol-4-yl)-4,5-Dihydropyrazoles Derivatives

“…Compared with traditional methods, this method is more convenient and easily controlled. A large number of organic reactions can be carried out in a higher yield shorter reaction time and milder conditions under ultrasound [48][49][50][51][52].…”