In this article, nitration reactions of 2-methyl-3(H)-quinazolin- 4-one using nitrating mixture (HNO +H SO ) were carried out

Аннотация

In this article, nitration reactions of 2-methyl-3(H)-quinazolin- 4-one using nitrating mixture (HNO +H SO ) were carried out. As a result, the 3 2 4 mobile hydrogen atom located in the sixth position of the benzene ring in 2- methyl-3(H)-quinazolin-4-ones is exchanged for the -NO group, resulting in the 2 corresponding 2-methyl-3(H)-6-nitroquinazolin-4-one as a result of electrophilic coupling reactions. synthesized. In the process of obtaining the synthesized product, a large amount of nitrating mixture waste is generated. This mixture was applied to the oxidation process of Angren mine lignite. Oxidation process in nitric acid concentration from 5 to 15%, weight ratio of coal (organic part); When studying HNO :H SO = 1:0.2:0.4 to 1:1:2, it was 3 2 4 shown that it is possible to increase the amount of humic acids in coal from 3.96% to 55.17%. Key words: heterocyclic compound, 2-methyl-3(H)-quinazolin-4-one, nitration, brown coal, oxidized coal, humic acid, fulvic acids Introduction. The analysis of the scientific articles published today worldwide shows that conducting scientific and practical research on the basis of synthetic heterocyclic compounds containing N, S, O heteroatoms is rapidly developing. Among such compounds, we can include the quinazolin-4-one compound, which can be isolated not only from the composition of plants, but also synthesized by various methods. The purpose of this research work is the conditions for increasing humic acids in coal in the presence of the nitrifying mixture formed during the synthesis of 2-methyl-6-nitro-3(H)-quinazolin-4-one in high yields. Literature analysis. In the course of our research, in the course of the analysis of literature sources, researches are being carried out in leading scientific centers of the world on obtaining new derivatives of bicyclic quinazolin-4-ones using modern organic synthesis methods, determining their biological activity and creating drugs with high pharmacological activity and less toxicological harm. This is due to the presence of bicyclic quinazolin-4-one and 156 ACADEMIC RESEARCH IN MODERN SCIENCE International scientific-online conference their derivatives with high biological activity and important organic compounds with analgesic, anti-inflammatory and anti-cancer activity in medicine. In addition, it can be explained by the fact that it is used in agriculture as a fungicide, pesticide, insecticide, plant growth stimulator, in the chemical industry as a raw material for the synthesis of various polymers and artificial fibers, and as raw materials for obtaining corrosive agents. [1-2]. In our previous studies, information on the optimal conditions and technology for the synthesis of 3(H)-quinazolin-4-one, which can be used as an anthelmintic agent in animal husbandry, is given [3]. In this research work, favorable conditions for the synthesis of 2-methyl-3(H)-6-nitroquinazolin-4-one, which is an important intermediate and exhibits high biological activity, are presented. Continuing the research, in the synthesis of 2-methyl-3(H)-6-nitroquinazolin-4-one, 2-methyl- 3(H)-quinazolin-4-one was synthesized in the presence of a nitrating mixture. The formation and purity of the synthesized compound was determined by the TLC method on Silufol UV-254 paper and recrystallized in ethyl alcohol. As a result, 3(H)-2-methyl-6-nitroquinazolin-4-one was synthesized with 87.4% yield. The course of the reaction equation and mechanism was proposed as follows (Figure 1). Figure 1. Nitration reaction of 2-methyl-3(H)-quinazolin-4-one The use of the above oxidizers to increase the yield of humic acids from brown coal creates additional technological difficulties in the application of inorganic and organic acids. This requires a large amount of water and a lot of time, as well as additional equipment in the process of washing coal. It is known from the literature that oxidation of lignite with nitric acid in the presence of acetic acid [4]. Accordingly, the coal was first treated in a mechanical lime with acetic acid in a coal:acetic acid ratio of 1:0.05 to 1:0.2 for 30 minutes, oxidation from 10 to 30% was carried out in nitric acid concentration up to Temperature 40 °C, duration 120 minutes and weight ratio coal:HNO = 1:2. After oxidation under optimal conditions, the GC content 3 increased to 66.1% 157 ACADEMIC RESEARCH IN MODERN SCIENCE International scientific-online conference The results of the study of oxidation processes of lignite obtained from the Angren mine with a mixture of nitric and sulfuric acids depending on various parameters are presented. The optimal process mode was found for the maximum yield of humic acids and minimum loss of nitrogen oxides. When coal was oxidized with a mixture of acids, the yield of humic acids increased significantly and reached 61.62%. In this work, we decided to test the oxidation process in the presence of a nitrifying mixture against Angren lignite. Analyzes and results. In the experiments, we obtain