Abstarct: Pyrimidines are an important class of nitrogen heterocyclic compounds with several applications such as anti-HIV, antibacterial, anticancer, and anti-viral properties. Similarly, 1,2,3-triazoles have an important role in medicinal chemistry, organic chemistry and chemistry of dyes due to their easy synthesis by click chemistry. In this work, some novel series of pyrimidines were synthesized via copper-catalyzed click reactions) and carbon-carbon sonogashira coupling reactions. 1. A series of novel 1,2,3-triazole-functionalized pyrimidines were prepared by the reaction of 4-propargyl-substituted-5-bromo-2-chloro-6-methylpyrimidine with aryl azides in the presence of phenylenediamine, as a ligand. This method offers the advantages of mild experimental conditions, operational simplicity, and good to high reaction yields. 2. A useful and efficient procedure was obtained for the synthesis of 1,2,3-triazole-lixnked pyrimidines via click reaction of propynylated pyrimidine and aromatic azides in the presence of Mg-Al-LDH-immobilized-CuI with high-to-excellent yields. Moreover, the prepared catalyst was characterized by the FT-IR spectroscopy, XRD, BET, SEM, and ICP techniques. 3. A novel derivatives of 4-(3-arylprop-2-ynyloxy)-6-methyl-2-(methylthio)pyrimidine were synthesized via the palladium-catalysed Sonogashira reactions of 4-methyl-2-(methylthio)-6-(prop-2-yn-1-yloxy)pyrimidine with aryl iodides in acetonitrile. 4. A new derivatives of 6-substituted-4-alkynylpyrimidine-5-carbaldehydes were synthesized through the Sonogashira coupling reactions of 6-substituted-4-chloropyrimidine-5-carbaldehydes and terminal acetylenes in the presence of PdCl2(PPh3)2 as a catalyst in acetonitrile at room temperature under argon atmosphere. The structures of all synthesized compounds were confirmed by the spectroscopic data such 13CNMR, 1HNMR, SEM, BET, FTIR and XRD.