Tetramethylguanidine-functionalized melamine as a multifunctional organocatalyst for the expeditious synthesis of 1,2,4-triazoloquinazolinones

• Published in: Scientific reports Vol. 11; no. 1; p. 14457
• Main Authors: Keshavarz, Mahnoush, Dekamin, Mohammad G, Mamaghani, Manouchehr, Nikpassand, Mohammad
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 14.07.2021; Nature Publishing Group UK; Nature Portfolio
• Subjects: Benzaldehyde; Catalysts; Chemistry; Nanoparticles; Scanning electron microscopy
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-91463-1

Novel nano-ordered 1,1,3,3-tetramethylguanidine-functionalized melamine (Melamine@TMG) organocatalyst was prepared and adequately identified by various techniques including FTIR, EDX, XRD and SEM spectroscopic or microscopic methods as well as TGA and DTG analytical methods. The Melamine@TMG, as an effective multifunctional organocatalyst, was found to promote smoothly the three-component synthesis of 1,2,4-triazoloquinazolinone derivatives using cyclic dimedone, 3-amino-1,2,4-triazole and different benzaldehyde derivatives in EtOH at 40 °C. This practical method afforded the desired products in high to excellent yields (86-99%) and short reaction times (10-25 min). The main advantages of this new method are the use of heterogeneous multifunctional nanocatalyst, simple work-up procedure with no need for chromatographic purification, highly selective conversion of substrates and recyclability of the catalyst, which could be used in five consecutive runs with only a small decrease in its activity.