Complexation of N-alkyl(aryl)- and N,N-dialkylcarbamoylmethylphosphine oxides with the f-elements

Abstract

Complexation of N alkyl(aryl)carbamoylmethylphosphine oxides (CMPO) and their N,N dialkyl analogs in neutral media was studied. N Alkyl derivatives react with praseodymium and europium nitrates both in solution and in the individual state to give 1 : 2 and 1 : 3 complex es, depending on the ratio of the starting reagents; for N aryl amides, 1 : 3 complexes were obtained only. With the uranyl cation, both N alkyl and N,N dialkyl derivatives of CMPO form various 1 : 1 complexes.Phosphorylacetamides, which are also referred to as carbamoylmethylphosphoryl compounds, are neutral or ganophosphorus complexing agents used in disposal of liq uid radioactive wastes. 1-4 Although complexes obtained in model experiments in neutral media often differ from com plexes produced in an organic phase during real extraction from acidic media, it is obvious that the design of more efficient extractants is impossible without an insight into the fundamental coordination chemistry of ligands em ployed in extraction systems. For this reason, the struc tures of f element complexes with known carbamoylme thylphosphoryl compounds have been examined by a num ber of researchers. 5-13For instance, in the study of the complexation between the phosphonates (RO) 2 P(O)CH 2 C(O)NEt 2 (L, R = Et and Pr i ) and f elements, the complexes UO 2 (L)(NO 3 ) 2 , 6 Th(L) 2 (NO 3 ) 4 , 7 Ln(L) 2 (NO 3 ) 3 (Ln = La-Gd), 8 and Ln(L) 2 (NO 3 ) 3 •H 2 O (Ln = Tb-Eu) 8 were isolated and characterized by spectroscopic methods or, in a number of cases, by a single crystal X ray diffraction. In the complex es of the first three types, the ligand is coordinated via O,O bidentate fashion, while in the last type, the Ln atom is coordinated to the ligand through the phosphoryl O atom and the carbonyl O atom is hydrogen bonded to the water molecule coordinated by the metal atom. 8 Ac cording to X ray diffraction data, N,N dimethyldiethoxy phosphorylacetamide (L = (EtO) 2 P(O)CH 2 C(O)NMe 2 ) also forms the lanthanide complexes Ln(L) 2 (NO 3 ) 3 (Ln = La, Sm, Yb, Er, Ce, Eu, and Gd) with bidentate coordination of the O atoms of the phosphoryl and carbo nyl groups. 9 Complexes of the uranyl cation with this ligand and its diphenylphosphoryl analog have a similar structure and a metal to ligand ratio of 1 : 1 (UO 2 (L)(NO 3 ) 2 ). 10

Synthesis and Coordination Properties of Tripodal Ligand on the Triphenylphosphine Oxide Platform with Carbamoyl Side Arms

“…In the complex NdL 2 (NO 3 ) 3 (L = (2-NCCH 2 OC 6 H 4 ) 3 PO), as was shown in our recent work, 36 34 NMR spectral study. As a whole, the data of NMR spectroscopy for complexes 3-5 agree well with the coordination modes supposed from the data of IR spectra.…”

“…Typical decrease in ν P O on coordination of phosphoryl-containing ligands in complexes with uranyl and lanthanide nitrates is 30-50 cm −1 . [31][32][33][34] The bands of ν C O change: a weak band remains in the region of vibrations of free C O groups (1664 cm −1 ) and a strong band appears at 1601 cm −1 that corresponds to vibrations of coordinated groups. One can suppose, taking into account intensity ratio, that two C O groups are coordinated in complex 3, while one group remains free.…”

Facile One-Pot Synthesis and X-ray Characterization of N-(Thio)phosphoryl-2-oxo-1,2-azaphospholanes: First Example of Cyclic O,O- and O,S-Bidentate Ligands with the P-N-P Backbone

“…Considerable downfield (U) or upfield (Eu) shifts of the signals in the 31 P NMR spectra of the corresponding complexes provide convincing evidence for the participation of both oxygen atoms of the P=O groups in the coordination. 17 Detailed results on the complexation features of the above ligands will be published elsewhere.…”

Conformational Analysis of N-Alkyl-N-[2-(diphenylphosphoryl)ethyl]amides of Diphenylphosphorylacetic Acid: Dipole Moments, IR Spectroscopy, DFT Study

“…Derivatives of carbamoylmethylphosphine oxides (CMPO) are known as effective extractants of rare earth elements and actinides from mineral acid solutions [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. The high coordinating ability of these compounds is due to the presence of polar phosphoryl and amide groups.…”

“…Although carbamoylmethylphosphine oxides have found active practical application for a long time, their spatial structure has been poorly studied. The literature contains data on the structure of complexes of CMPO with rare earth elements and actinides [ 17 , 29 , 30 ], manganese (II) [ 27 ], and mercury (II) [ 31 ] in the solid state. The crystal structures of (diethylcarbamoyl)methyldiphenylphosphine oxide and its protonated form [ 32 ], diphenylmorpholine carbamoylmethyl phosphine oxide [ 33 ], diphenyl- N , N -dimethylcarbamoylmethylphosphine oxide [ 34 ], N -aryl-substituted CMPO modified with a phosphoryl group, and its complexes with Pd (II) and Re (I) [ 35 ] were determined by X-ray diffraction.…”