592-35-8Relevant articles and documents
PROCESS FOR THE SYNTHESIS OF ISOCYANATE-FREE OMEGA-HYDROXY-URETHANES, ALPHA-OMEGA-DIURETHANES AND OLIGO (POLY)URETHANES
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Page/Page column 10, (2021/11/26)
The synthesis of omega-hydroxyalkyl-urethanes, and of alfa-omega-diurethanes is reported which includes the reaction of diols with urea in presence of catalysts based on Ce at temperatures between 125 and 170°C over 4-8 h reaction time. A process for the production of oligomers of omega-hydroxyalkyl-urethanes is also reported based on the reaction of urea with diols in presence of Ce or Zr catalysts or Ce mixed oxides at 125-170°C over 4-20 h.
Preparation method of carbamate
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Paragraph 0048; 0052-0054, (2020/09/23)
The invention belongs to the technical field of synthesis of amino and carboxyl compounds connected to the same carbon frame through urea alcoholysis, and particularly relates to a preparation methodof carbamate. The preparation method of the carbamate comprises the following steps of: sequentially introducing urea, alcohol and a catalyst into a reactor, sealing, and reacting at 90-120 DEG C for8-12 hours to obtain the carbamate, wherein the catalyst includes an alumina supported metal oxide. By adopting the method for preparation of the carbamate, the side reaction of urea decomposition canbe effectively avoided, impurities such as carbamate are not detected, and the yield of the carbamate is high.
An efficient one-pot synthesis of industrially valuable primary organic carbamates and: N -substituted ureas by a reusable Merrifield anchored iron(ii)-anthra catalyst [FeII(Anthra-Merf)] using urea as a sustainable carbonylation source
Basu, Priyanka,Dey, Tusar Kanto,Ghosh, Aniruddha,Biswas, Surajit,Khan, Aslam,Islam, Sk. Manirul
, p. 2630 - 2643 (2020/02/20)
An efficient synthesis of primary carbamates and N-substituted ureas is explored with a newly developed heterogeneous polymer supported iron catalyst in the presence of a sustainable carbonylation source. The Merrifield anchored iron(ii)-anthra catalyst [FeII(Anthra-Merf)] was synthesized by functionalization of Merrifield polymer followed by grafting of iron metal. The catalyst [FeII(Anthra-Merf)] was characterized by several techniques, like SEM, EDAX, TGA, PXRD, XPS, FTIR, CHN, AAS and UV-Vis analysis. The designed polymer embedded [FeII(Anthra-Merf)] complex is a remarkably successful catalyst for the synthesis of primary organic carbamates and N-substituted ureas by using safe carbonylation agent urea with different derivatives of alcohols and amines, respectively. The reported catalyst is a potential candidate towards contributing a satisfactory yield of isolated products under suitable reaction conditions. The catalyst is recyclable and almost non-leaching in nature after six runs with an insignificant drop in catalytic activity. Thus we found an economical and viable catalyst [FeII(Anthra-Merf)] for primary carbamates and N-substituted urea synthesis under moderate reaction conditions.
