Amides uranium

The literature is most prolific on neutral An amides, but neutral U and amides are also well documented. There are only few publications on amides,one being on three alkali metal amidouranate(VI)s. ° There is a paper on a compound (18) which couid be classified as of U° and two on mixed valence U /U amides (see Section 5.4 for these types). There are a number of articles on monocationic amidol/ tetraphenylborates, three on dicationic analogues, three on a cationic U salt and four on alkali metal amidoactinate(IV)s and three on corresponding U salts. For crystalline uranium amides containing only monodentate ct-bonded ligands, metal coordination numbers of 3-7 are... 

Substituent effects, 9 510 Substituted alkylhydrazines, 13 572-573 Substituted amide waxes, 26 221 Substituted cyclopentadienyl uranium complexes, 25 440-441 Substituted cyclopentadienyl (Cp)... 

The molecular structure consists of three discrete AICI4 tetrahedra and a benzene ring bound to the uranium atom. The coordination around the metal center can be viewed roughly as a pentagonal bip o amid with five equatorial chlorines, an apical chlorine and an apical benzene ring. This coordination is only approximate since the uranium atom lies roughly 0.5 A out of the plane of the equatorial chlorines. The mean AI—Cl distance for the chlorines bonded to the uranium is 2.18 A and 2.09 A for the others. The mean U—C distance is 2.91 A. 

Several complexes with ligands related to amides, such as lactams, lactones and antipyrine (atp) have also been recorded (Table 77) apart from preparative and IR spectroscopic information, little is known about them. The precipitation of U02(NCS)2-3atp from aqueous acid in the presence of thiocyanate has been used as a method for the determination of uranium in minerals. 

Suzuki, S., Tamura, K., Tachimori, S., Usui, Y. 1999. Extraction of uranium(VI) and plutonium(IV) from nitric acid solution by substituted cyclic amides. Solvent Extr. Res. Dev. Jpn. 6 72-79. 

Vidyalakshmi, V., Subramanian, M.S., Srinivasan, T.G., Rao, P.R.V. 2001. Effect of extractant structure on third phase formation in the extraction of uranium and nitric acid by N,N-dialkyl amides. Solvent Extr. Ion Exch. 19 (1) 37 -9. 

Suzuki, S., Yaita, T., Sugo, Y., Kimura, T. 2007. Study on selective separation of uranium(VI) by new N,N-dialkyl carboxy amides. GLOBAL 2007, Boise, ID, September 9-13. 

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