New preparation method of O-methyl isourea methyl sulfate

Abstract

The invention discloses a new preparation method of O-methyl isourea methyl sulfate. The method includes the following steps that a certain amount of dimethyl sulphate is added in a 500-mL three-mouthreaction bottle, quantitative urea is added in batches, after reaction liquid is clear, a thermal insulation reaction is conducted for a certain time, and the product, namely O-methyl isourea methylsulfate, is obtained. Urea and dimethyl sulphate are adopted as raw materials for the reaction under the microwave effect to prepare O-methyl isourea methyl sulfate. The method has the advantages thatthe reaction can smoothly occur at the low temperature at which a conventional method is difficult to conduct, the reaction time is largely shortened, and the reaction efficiency and the product purity are improved; the temperature is controlled to be 45-70 DEG C, reduction of the reaction temperature not only can reduce the safety risk, but also can reduce side reactions in the production process, and the product yield is thus increased to 80%.

Description

technical field [0001] The invention belongs to the technical field of chemistry and relates to a new method for preparing O-methylisourea methyl sulfate. Background technique [0002] O-methylisourea (OMIU for short) is a synthetic intermediate widely used in the fields of medicine, pesticides and materials. The substance is a colorless crystal with the molecular formula C 2 h 6 N 2 O, molecular weight 74.08, melting point 44-45 ℃, can absorb moisture and carbon dioxide in the air. O-methylisourea is very unstable, so it is often sold and used in the form of salt. In view of its specific molecular structure, O-methylisourea is a good "precursor" for the synthesis of guanidines, imidazoles, (ura)pyrimidines and their derivatives, and many of these substances have good biological properties. activity, thus contributing to the wide application of O-methylisourea (salt) in fields such as medicine and pesticides. [0003] O-methylisourea methyl sulfate is a kind of O-methy...

AI Technical Summary

Problems solved by technology

In the conventional method, the reaction temperature is low, and the reaction speed of the raw materials is slow or even hardly reacts. In order to promote the smooth progress of the reaction, the reaction temperature needs to be increased to above 70°C, but the high temperature leads to a decrease in the stability of the system, and a sharp increase in the system temperature is likely to cause safety hazards. At the same time, when the high temperature reaction is performed, the side reaction will increase significantly, and the product yield will decrease

The existing conventional process controls the reaction temperature at 70-120°C, and the product yield is about 64%.