Ultrasound-assisted one-pot synthesis of 1,3-oxazine derivatives catalysed by BF3-SiO2 under neat conditions

Abstract

An efficient and environment-friendly method for the synthesis of 1,3-oxazine derivatives has been developed using the ultrasound-mediated condensation of 2-naphthol with formaldehyde and primary amines under solvent-free condition at room temperature in the presence of BF 3-SiO2 to give the desired product in good to excellent yield. This procedure provides several advantages over current methods including a simple work-up, cost effectiveness, a reusable catalyst and shorter reaction times.