Study On N,N’-Dimethyl-2-Imidazolidinone Synthesis Process And Application

1,3-Dimethyl-2-Imidazolidinone (DMI) is a new type of polar aprotic solvent.It has the very good dissolving ability for many compounds (such as resin materials, inorganic compounds, organic compounds), and good stability, low toxicity, high flash point,easy recovery. And the important point is easy to recycle. Based on investigation of a large number of domestic and foreign literatures, the physicochemical properties, the synthetic route and application fields of DMI were discussed in detail.In this paper,2-imidazolinone was prepared from Urea and ethylenediamine using water was used as the solvent and catalyst.1,3-Dimethyl-2-Imidazolidinone was prepared by the N-methylation reaction of2-imidazolone with formic acid which was used as solvent and methylation reagent. By optimizing the reaction solvent, reflux time, raw material ratio, catalys and methylation reagent, a suitable for China’s chemical manufacturing level, green, environmentally friendly DMI synthesis route was obtained finally. By detecting purity and analyzing structure with UV, HPLC, IR, MS and NMR, the product was consistent with the target product. Then the magnified experiment validated the stability of the process, and we obtained better "three discard" treatment processes for the industry "three discard" generated in the process.DMI process route:dissolve ethylenediamine:urea:water (molar ratio1\1.05\1.66) by heating to120℃, reaction for3hours under reflux, recovery ammonia, attain2-imidazolinone by curing dissolved;2-imidazolinone:formaldehyde:dissolve formic acid (molar ratiol:2.2:7.5) by heating to105℃reaction for12hours under reflux, recovery formic acid at120℃, vacuum distillation collection (30mmHg) DMI.Trimethoprim (TMP) is one of the pillars of China’s pharmaceutical industry products, and3-(phenylamino)-2-(3,4,5-trimethoxy benzyl) acrylonitrile is a key intermediate for preparation of TMP. In This paper,3-(phenylamino)-2-(3,4,5-trimethoxy benzyl) acrylonitrile was synthesized from dimethylamino-propionitrile, trimethoxybenzaldehyde, aminobenzene, aniline in DMI. Through a large number of experiments to the reaction solvent, reflux time and raw material ratio, a synthetic route suitable for China’s chemical manufacturing level, green, environmental protection was ultimately obtained.And then through the detection and analysis of purity and structure with IR, MS and NMR, the product was consistent with the target product. The experimental results showed that DMI as a reaction solvent has the following advantages:not easy to decompose, low toxicity. In addition, the product prepared in DMI had higher yield and larger particle size which was easy to crystallization and dry.