Abstarct: Pyrimidin-2(1H)-one is a six membered aromatic heterocycle with two nitrogen atoms at 1 and 3 positions in the ring. Its derivatives have wide occurrence in nature, in particular, thiamine and the nucleotides. Many synthetic of pyrimidines such as barbiturates (e. g. thiopental sodium) and HIV drugs (e. g. zidovodine) and several other pharmaceuticals are also known. The antimicrobial activities of the synthesized compounds have been studied against the cultures “staphylococcus aureus”, “esherichia coli”, “candela albicans”. The general method in Biginelli reaction usually start using ethyl acetoactate, an aryl aldehyde and urea. However to the best of our knowledge no reaction using CoCl2 /KI has been reported. This method can be equally applied to heteroaryl and substituted aryl aldehydes. The yields of the reactions under these conditions are usually high and the compounds have been characterized using spectroscopic methods IR, FT-IR, NMR and Mass spectrometry.