Iranian researchers from Mazandaran University synthesized zinc oxide nanoparticles with high catalytic activity to simplify the reaction condition for the formylization of amines, using mechanochemical methods and without utilizing solvents. In order to carry out the research, the catalyst of zinc oxide nanoparticles was prepared as the raw material by using zinc acetate and oxalic acid through mechanochemical method. We mixed zinc acetate and oxalic acid in an agate mortar with molar ratio of 3:2. The obtained white powder turned into zinc oxide nanoparticles in the oven after being calcinated. Then, various derivatives of formaldehydes were synthesized from ortho-phenylene diamines and formic acid without using solvent in the presence of zinc oxide nanoparticles catalyst. Zinc oxide nanoparticles catalyst was synthesized through a cost-effective and simple mechanochemical method. No solvent was used in the production of this catalyst. This fact resulted in the reasonable price and availability of the raw materials for the production of zinc oxide nanoparticles, and also in higher catalytic activity in the catalyst. Reaction conditions to synthesize formamides from amines change into mild conditions with low reaction time when this catalyst is used, and the yield of the reaction increases as well. Among other advantages of the catalyst, mention can be made of the very simple separation of the product and very tiny amount of the waste during the separation. Results of the research have been published in Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry, vol. 43, issue 5, 2013. For more information about the details of the research, study the full paper on pages 532-538 on the same journal.