| 초록 |
Disubtituted urea, a versatile class of organic compounds, has been widely used as intermediates in pharmaceuticals, agrochemicals, pigments and potential precursors of both carbamates and isocyanates. Conventionally, the preparation of urea involves either the toxic phosgenation or potentially explosive oxidative and reductive carbonylation of amines. In a continuous effort to develop eco-friendly alternative process to urea through the utilization of CO2, a set of novel and well-prepared Cesium azolides were investigated as highly efficient catalysts for the carboxylation of amines and CO2. Experimental variables for the optimization such as temperature, CO2 pressure, solvents and reaction time were also studied. The results indicated that these novel Cesium-azolide catalysts could facilitate the carboxylation of amine to provide various disubtituted urea with high selectivity in the absence of any dehydrating agents. |
