Green synthesis of dihydropyrimidine based on cinnamaldehyde compound under solvent-free using graphene oxide as catalyst

Cinnamaldehyde is an essential compound in the cinnamon that have plentiful bioactivities. This research aims to modify cinnamaldehyde to become derivatives of dihydropyrimidine using graphene oxide (GO) as catalyst. GO was synthesized from graphite powder. Afterward, GO was applied in dihydropyrimidine synthesis with one-pot three-component method without solvent. The Fourier transform infrared (FTIR) spectra has proven the formation of GO (3119 cm−1, 1723 cm−1, 1373 cm−1, and 1076 cm−1). To evaluate the ability of GO as catalyst, one synthesized compound with the name 6-methyl-5-propionyl-4-styryl-3,4-dihydropyrimidin-2(1H)-one was obtained. Then, the synthesized compound was analyzed for its absorbance, functional group, and molecular weight using UV/Vis spectrophotometry, FTIR and GC-MS. The best condition of reaction is with the in condition of catalyst 7.5 %, temperature 100 °C, and reaction time 30 minutes. In this condition, the product yield is 83.7 %.