109-77-3Relevant articles and documents
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Ardis et al.
, p. 1305 (1950)
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Cyanocarbon Acids: Direct Evidence That Their Ionization Is Not an Encounter-Controlled Process and Rationalization of the Unusual Solvent Isotope Effects
Hojatti, M.,Kresge, A. J.,Wang, W.-H.
, p. 4023 - 4028 (1987)
The rate of exchange of the acidic hydrogen of tert-butylmalononitrile was examined by using as a tracer, and the process was found not to be inhibited by hydronium ions in dilute aqueous hydrochloric acid solutions.This rules out the Swain-Grunwald mechanism for this reaction under these conditions.The bromination of malonitrile was investigated under conditions where reprotonation of the dicyanomethyl carbanion and its reaction with bromine occur at comparable rates, and the bromination reaction was found to have a specific rate twice that for reprotonation.Reprotonation therefore cannot be a diffusion-controlled process, and malonitrile is not a "normal" acid.The unusually large solvent kinetic isotope effects found for these cyanocarbon acid ionization reactions are explained by postulating that the transferring hydrogen and its positive charge are becoming associated with a solvent cluster rather than with a single water molecule.The thermodynamic acidity constant of malonitrile was determined to be 11.41 in aqueous solution at 25 deg C.
Preparation method of malononitrile and malononitrile prepared by preparation method
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Paragraph 0056-0103, (2021/05/01)
The invention relates to the technical field of chemical synthesis methods, particularly to a malononitrile preparation method and malononitrile prepared thereof. The malononitrile preparation method comprises the following steps: mixing cyanoacetamide, a catalyst and a solvent, heating, refluxing, and introducing phosgene to synthesize malononitrile, wherein the mass ratio of the cyanoacetamide to the catalyst to the solvent is (2.5-3.5):(0.005-0.02):(7.5-10.5), the solvent is any one of dichloromethane, dichloroethane or methylbenzene, and the catalyst is any one or more of diethylamine, N,N-dimethylformamide or pyridine. According to the invention, cyanoacetamide is adopted to synthesize malononitrile in one step under the action of phosgene, wherein the required raw materials are cheap and easy to obtain, the synthetic reaction steps are few, harsh conditions are avoided, the operation is simple, stable and good in controllability, and the yield of the prepared malononitrile can reach 93% or above and is far higher than that of malononitrile obtained through other process schemes; and the preparation method is low in three-waste treatment cost, and has objective economic benefit.
Malononitrile preparation method and malononitrile prepared thereof
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Paragraph 0056-0095; 0103, (2020/08/02)
The invention relates to the technical field of chemical synthesis methods, in particular to a malononitrile preparation method and malononitrile prepared thereof. The malononitrile preparation methodcomprises the following steps that cyanoacetamide, a catalyst and a solvent are mixed, heated, refluxed and introduced with phosgene, and malononitrile is synthesized, wherein the mass ratio of the cyanoacetamide to the catalyst to the solvent is (2.5-3.5):(0.005-0.02):(7.5 to 10.5); the solvent is any one of dichloromethane, dichloroethane or methylbenzene; and the catalyst is any one or more ofdiethylamine, N, N-dimethylformamide or pyridine. According to the invention, cyanoacetamide is adopted to synthesize malononitrile in one step under the action of phosgene; the method has the advantages of cheap and easily available required raw materials, few synthesis reaction steps, no harsh conditions, simple operation, stability and good controllability, the yield of the prepared malononitrile can reach 93% or above and is far higher than that of other process schemes, and the preparation method has the advantages of low three-waste treatment cost and objective economic benefits.
Synthetic method of malononitrile
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Paragraph 0011-0030, (2020/01/08)
The invention belongs to the technical field of organic synthesis, and provides a malononitrile synthesis method. The synthetic method comprises the following steps: adding dichloromethane and sodiumcyanide into a reaction kettle at a molar ratio of (1: 1)-(3: 1), slowly adding a catalyst into the reaction kettle under stirring and heating conditions, controlling the temperature in the reaction kettle to be 90 DEG C, and carrying out thermal preservation reaction for 5-9 hours after feeding is finished; after the reaction is finished, adding deionized water into an obtained reaction product to wash an organic phase for a plurality of times, separating out the organic phase, drying the organic phase, and rectifying to obtain malononitrile; wherein the catalyst is a composition of aluminumtrichloride and tetrabutylammonium bromide. According to the method, the malononitrile product is directly synthesized by taking cheap dichloromethane as a raw material through a one-step method, theprocess route is simple, and the cost is low.