Shape-controlled synthesis of sodium zincate mesoporous structures based on sulfonated melamine formaldehyde and their application as catalysts for Biginelli reaction

Abstract

In the current research, two mesoporous structures of sodium zincate [Na2Zn(OH)4], spheres and aggregated particles, has been synthesized from sulfonation of melamine-formaldehyde (MF) and then bounding [Na2Zn(OH)4] particles onto the surface of sulfonated melamine–formaldehyde (SMF). Furthermore, in the present synthetic methodology the zinc oxide (ZnO) thin films on sulfonated melamine–formaldehyde was formed via the chemical deposition, and thermal treatment techniques of the sodium zincate. Several spectroscopic and analytical methods proved the structural and morphological properties of sodium zincate mesoporous structures based on sulfonated melamine formaldehyde [SMF/Na2Zn(OH)4]. The experimental studies showed that these catalytic systems showed high activity in the Biginelli reaction for the synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives and will find recoverable potential application. The obtained results indicated that the synthesized mesoporous structures had a thermal stability near 300 °C, particle-size distribution around of 10–120 nm for spheres and the surface area of 6 and 2 m2/g for spheres and aggregated particles, respectively.