Study On The Synthetic Process And Dynamics Of 4,6-dihydroxy Pyrimidine

Pyrimidine compounds as anti-fungal and promote the plant growth, and widely used in the preparation of medicine and pesticides.4,6-dihydroxy pyrimidine is an important intermediate for the sythesis of pyrimidine compounds. A systematic experimental study is conducted on technology of the synthesis process according to the problem of producing 4,6-dihydroxy pyrimidine.In this paper, the thermodynamic data of synthesis reaction of 4,6-dihydroxy pyrimidine were calculated and its chemical equilibrium constant was obtained, what provided basis for the design of the process conditions and production.The optimization process conditions were obtained with orthogonal experiments and single factor experiments design taking Dimethyl malonate and Formamide as raw materials, the optimization process conditions are as fllows:reaction temperature is 50℃, reaction time is 3 h, the concentration of sodium methonate is 30%, n (dimethyl malonate):n (formamide):n (sodium methoxide)= 1:2.6:3. Under this technological conditions, the yield of 4,6-dihydroxy pyrimidine is 82.09%, Structure of the yield was confirmed by IR spectra. The optimized synthesis process provides several advantages such as shorter reaction time, less raw material, milder conditions and easier operation.The kinetic of the synthesis reaction system was studied using isothermal method, and the yield of reaction product was measured at different time, and the kinetic equation was obtained in this test which accurately described the change of the yield with reaction time, reaction temperature and material molar ratio, the parameters of the kinetic models were established with experimental data. It was found that all kinetic models were two-order irreversibility reaction under the conditions of this experiment. Its reliability was confirmed by the performance test, which provides experimental evidence for industrial production.