Preparation method and application of N-bis (dimethylamino)-1, 3-dimethylimidazoline

Abstract

The invention relates to the field of preparation methods and application of compounds, in particular to a preparation method and application of N-bis (dimethylamino)-1, 3-dimethylimidazoline, whereinthe chemical molecular formula is C9H23N5. The preparation method comprises the following steps: S1, taking 1, 3-dimethyl-2-imidazoline and bis (trichloromethyl) carbonate as raw materials, and carrying out chlorination reaction to synthesize chlorinated 1, 3-dimethyl-2-chloroimidazoline; therefore, the problems of safety and environmental protection of other chlorinated reagents are solved, andthe product yield (87% or above) is greatly improved. S2, dropwise adding tetramethylguanidine into the generated chlorine salt, and carrying out condensation reaction; S3, carrying out neutralizationreaction on an obtained product to obtain N-bis (dimethylamino) methylene-1, 3-dimethyl-2-chloroimidazoline ammonium chloride salt. The process is high in operability, mild in reaction condition, safe, green, environmentally friendly, good in product catalytic effect and wide in application range, and almost no other impurities are generated except that high-content potassium chloride is generated as a byproduct.

Description

Technical field [0001] The invention relates to a compound preparation method and application field, in particular to a preparation method and application of N-bis(dimethylamino)-1,3-dimethylimidazoline. Background technique [0002] In the preparation of aromatic fluorine-containing compounds by the halogen exchange method, since the reaction is a heterogeneous reaction, a phase transfer catalyst needs to be added to act as a medium for the transfer of F- in the solid-liquid two-phase to increase the solubility of F- in the liquid phase. Promote the fluorination reaction. Due to the electricity absorption of the cyano group, the ortho-para position chlorine atom of the benzene ring is easier to fluorinate, but the meta-substituted chlorine atom is inert and difficult to activate the fluorination. It needs a higher temperature to proceed. Ordinary phase transfer catalyst Low catalytic activity, poor temperature resistance, easy to decompose at high temperature, resulting in exce...

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Problems solved by technology

Quaternary ammonium salts will decompose when the temperature is slightly higher, and cannot play the role of catalytic fluorination at higher temperatures. Although the thermal stability of quaternary phosphonium salts and crown ethers is better than that of quaternary ammonium salts, their catalytic activity is not high. The substitution effect on the chlorine on the meta position is very small at high temperature

[0004] When carrying out the chlorination reaction, the method for preparing chlorinated 1,3-dimethyl-2-chloroimidazoline with phosgene, diphosgene, oxalyl chloride, etc. as the chlorination reagent in the early stage, the yield of these three methods is low, Moreover, phosgene and diphosgene are highly toxic, and oxalyl chloride is a highly corrosive liquid, which poses great safety hazards in production and transportation.

[0005] There are also reports of preparing chlorinated 1,3-dimethyl-2-chloroimidazolines with chlorination reagents such as phosphorus trichloride, phosphorus pentachloride, phosphorus oxychloride, but the use of this type of reagent makes the reaction system appear in two ways. Phase state, and the existence of by-product phosphoric acid in the reaction, so that it is difficult to fully carry out the reaction, and it is difficult to separate the products

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