A viable and efficacious catalyst, CeO2/HAp, for green synthesis of novel pyrido[2,3-d]pyrimidine derivatives

摘要

A facile one-pot green protocol at room temperature has been devised for the synthesis of novel pyrido[2,3-d]-pyrimidine derivatives catalyzed by CeO2-doped hydroxyapatite (CeO2/HAp) with ethanol as solvent. This highly selective method with excellent yields (89-96%) involves a four-component reaction between malononitrile, substituted aldehyde, dimethylbarbituric acid and ammonium acetate. CeO2/HAp was synthesized and characterized by P-XRD, TGA, TEM and SEM analyses. The structures of the target molecules were confirmed by diverse spectroscopic methods (H-1 NMR, N-15 NMR, C-13 NMR, and HRMS). Additional benefits of this eco-friendly approach are the operational simplicity, a stable catalyst with good reusability (at least 6 times), short reaction times ( 45 min) and no need for chromatographic separations. All these features make the proposed method economical and sustainable.