Uranyl nitrate complexes of camphene-derived organophosphorus ligands, and the X-ray crystal structure of [UO2(NO3)(2)(RPO3Me2)(2)] (R = endo-8-camphanyl)

摘要

endo-8-Camphanylphosphinic acid [(2,2-dimethylbicyclo [2.2.1] hept-3-ylmethyl)phosphinic acid] camPO(2)H(2) 1 is readily oxidised to the corresponding phosphonic acid camPO(3)H(2) 2, the preferred reagent being SO2 in refluxing isopropanol. Methylation of the phosphonic acid 1 with diazomethane yields the methyl ester camPO(3)Me(2) 4. Oxidative chlorination of camPO(2)H(2) with SOCl2 produces the phosphonic dichloride camP(O)Cl-2 3, which gives the tertiary phosphine oxide camP(O)Ph2S on reaction with PhMgBr. The phosphonate ester 4 and phosphine oxide 5 readily form complexes 6 and 7 respectively with uranyl nitrate. The phosphonate complex 6 has been subjected to a single-crystal X-ray diffraction study. The structure determination was not straightforward, largely as a result of the combination of a dominant:scattering atom (uranium) and substantial disorder of the camphanyl groups. (C) 1998 Elsevier Science Ltd. All rights reserved. [References: 24]