The green synthesis and fluorescent properties of N1-substituted 3,4-dihydropyrimidinones derivatives
SONG Zhiguo1, JIANG Hongxu2, ZHANG Shun2, WANG Min2*
(1 Center of Experimental Management, Bohai University, Jinzhou 121013, Liaoning, China; 2 College of Chemistry and Chemical Engineering, Bohai University, Jinzhou 121013, Liaoning, China)
Abstract:
The Biginelli one-pot synthesis of N1-substituted 3,4-dihydropyrimidin-2(1H)-ones from aromatic aldehyde, methyl (ethyl) acetoacetate and monosubstituted urea in the presence of crystalline aluminium chloride at 80 ℃ without solvent was reported. The effects of the molar ratio of raw materials, the catalyst dosage and the reaction temperature on the reaction were investigated. The optimum reaction conditions were determined as follows: n (aromatic aldehyde) ∶n (acetoacetate) ∶n (monosubstituted urea) =1∶1∶1.3, crystalline aluminium chloride is 5 mol%, reaction temperature is 80 ℃. The target products were characterized by 1H NMR, 13C NMR, elemental analysis and X-ray single crystal diffraction techniques. In addition, the fluorescence property in the solid state was also studied. The results indicated the target compounds have good fluorescent properties. The maximum emission wavelength is 450-500 nm upon excitation at 373 nm.
KeyWords:
Biginelli reaction; 3,4-dihydropyrimidinones; crystalline aluminium chloride; fluorescence
