5259-97-2Relevant 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 6-7, (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.
Synthesis of urea derivatives from amines and CO2 in the absence of catalyst and solvent
Wu, Chaoyong,Cheng, Haiyang,Liu, Ruixia,Wang, Qiang,Hao, Yufen,Yu, Yancun,Zhao, Fengyu
experimental part, p. 1811 - 1816 (2011/02/22)
Urea derivatives are obtained in mild to good yield from the reactions of primary aliphatic amines with CO2 in the absence of any catalysts, organic solvents or other additives. To optimize reaction conditions, experimental variables including temperature, pressure, the concentration of amine, reaction time etc. were studied. Satisfactory yields were obtained at the optimized conditions that are comparable to the presence of catalyst and solvent. The preliminary investigation of the reaction mechanism showed that alkyl ammonium alkyl carbamate was quickly formed as the intermediate, and then the final product was formed by the intramolecular dehydration.
Formation of Cyclic Urethanes from Amino Alcohols and Carbon Dioxide Using Phosphorus(III) Reagents and Halogenoalkanes
Kubota, Yasuhiko,Kodaka, Masato,Tomohiro, Takenori,Okuno, Hiroaki (Yohmei)
, p. 5 - 6 (2007/10/02)
Cyclic urethanes are obtained in good yields under mild conditions from amino alcohols and carbon dioxide using phosphorus(III) reagents and halogenoalkanes (CCl4 and CCl3CCl3).
