N-Dlpheeylphosphorylureas on the Basis of Natural α-Amino Acid Esters: One-Pot Synthesis and Extraction Properties

摘要

We have shown recently that N-(diorganylphos-phoryl)ureas R2P(O)NHC(O)NHR' (I), especially N-diphenylphosphorylated derivatives (Ia, R = Ph), are high-performance extractants for the recovery of actinides and lanthanides from nitric acid solutions [1]. To date, extraction properties were studied for ureas Ia containing alkyl, aralkyl, and cycloalkyl groups as substituent R' at the terminal nitrogen; N-diphenylphosphoryl-N'-n-alkylureas (DPPAUs) Ph2P(O)NHC(O)NHAlk prepared from commercially available and cheap n-alkylamines was found to be the most efficient extractants [1-3], which considerably exceed in efficiency and selectivity structurally related diphenyl(carbamoylmethyl)phos-phine oxides [1].