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Information × Registration Number 0221U104856, 0120U105441 , R & D reports Title To study the reactivity of CH2N2 precursors (NMU, MNNG, Diazald) in relation to treatment with aqueous alkalis. Measure the solubility of CH2N2 precursors in water. popup.stage_title Head Ryabukhin Sergey V., Доктор хімічних наук Registration Date 25-04-2021 Organization Taras Shevchenko National University of Kyiv popup.description2  Object of study: Diazomethane. Purpose: among the known and available precursors of CH2N2 synthesis (NMU, MNNG, Diazald) to choose the best for further use in the generation of diazomethane in the conditions of duct chemistry. Research methods: organic synthesis, analysis using physical methods. The behavior of a number of classical diazomethane precursors such as: N-nitroso-N-methylurea (NMU), methylnitronitrosoguanidine (MNNG) and N-methyl-N-nitroso-para-toluenesulfonamide (Diazald) has been studied under suitable conditions. It was found that the interaction with concentrated alkali solutions (NaOH, KOH) at 0-5ºC leads to the rapid formation of diazomethane only in the case of using NMU. For other precursors, a significant release of the target compound, which would be sufficient to ensure the desired flow rate, is observed only at higher temperatures, which is incompatible with the design of the reactor. The solubility of NMU in water and organic solvents was investigated in order to find the optimal carrier of the diazomethane flow. According to the results of solvent optimization, the system dichloromethane: tetrahydrofuran 2: 1 was found, which satisfies all criteria for a potential flow carrier: high solubility of the substrate, inertness to diazomethane and alkalis, poor solubility in water, high surface tension, interface / solution low viscosity. As a result, the optimal source for generating diazomethane - NMU, and the optimal flow carrier system dichloromethane: tetrahydrofuran 2: 1. The results of the study were used to optimize the generation of diazomethane and the synthesis of its transformation products in a flow reactor by the main executors of the project at the Institute of Organic Chemistry of the National Academy of Sciences of Ukraine. Product Description popup.authors Nosyk Pavlo S. popup.nrat_date 2021-04-25 Close