Phenyl phosphine oxide moiety

Fluorinated PAEs with Phenyl Phosphine Oxide Moiety... 

The replacement of the phenyl groups on the phosphine oxide moieties by n-butyl groups leads to a complete loss of extraction. Increasing the length of the chain linking the calixarene to the phosphine oxide moieties leads to a decrease of extracting ability of both tetramer and hexamer (Table 4.23). The selectively substituted... 

The strong phenyl carbon signals in the 128 to 141 ppm region of the NMR spectra shown in Fig. 25.4 might have been expected to consist of four components at about 128, 131, 133 and 141 ppm, due to the various aromatic carbon sites, according to a previous study on diphenylethylphosphine moieties immobilized on silica gel via surface modification [61], The chemical shifts anticipated for the various aromatic carbon sites are shown below for immobilized phosphine and phosphine oxide moieties [61] ... 

Bis(2-hydroxypropyl)(phenyl)phosphine oxide 121 is a suitable chiral precursor for the synthesis of l-phospha-ll,12-benzo-21-crown-7 123 and l-phospha-10-aza-18-crown-6 122 derivatives, the first examples of optically pure, crown-ether-like, phosphorus-containing macrocycles (Scheme 12.47). The com-plexation of Na" by the crown ether moiety of the macrocyclic ring has been observed [107]. 

Extractants derived from the carbamoylmethylphosphoryl moiety (CMP) were studied in the phosphonate, phosphinate, and phosphine oxide classes. Our studies focused on dihexyl-N,N-diethylcarba-moylmethylphosphonate, DHDECMP, hexyl hexyl-N,N-diethylcarbamoyl-methylphosphinate, HHDECMP, and octyl(phenyl)-N,N-diisobutylcarba-moylmethylphosphine oxide, 0D[ IB]CMP0. The three types of CMP extractants were compared on the basis of nitric acid and extractant dependencies for Am(III), solubility of complexes on loading with Nd(III) and U(VI), and selectivity over fission products. On the basis of the above data two conceptual flowsheets were developed. The first flowsheet involves the extraction of all of the actinides from HLLW using 0.4 M 0D[IB]CMP0 in DEB. The second flowsheet involves the extraction of all of the actinides from dissolved spent LWR fuel using 0.8 M DHDECMP in DEB. 

Catalysts (25) are the Lewis acid-Lewis base bifunctional catalysts in which Lewis acid-Al(III) moiety activates acyl iminium ion and the Lewis base (oxygen of phosphine oxide) does TMSCN, simultaneously (Scheme 5.7). Halogen atoms at the 6-position enhanced both yields and enantioselectivity in Reissert-type cyanation of the imino part of 26. However, the order for the activation is not parallel to the electronegativity of the halogen atoms and, moreover, the strong electron-withdrawing trifluoromethyl group provided unexpectedly the worst result for the activation [13]. It is not simple to explain this phenomenon only in terms of the increased Lewis acidity of the metal center. Trifluoromethylated BINOL-zirconium catalysts (28) for asymmetric hetero Diels-Alder reaction (Scheme 5.8) [14], trifluoromethylated arylphosphine-palladium catalyst (32) for asymmetric hydrosilylation (Scheme 5.9) [15], and fluorinated BINOL-zinc catalyst (35) for asymmetric phenylation (Scheme 5.10) [16] are known. 

Organosilanes bearing a phosphine imide moiety have been synthesized from phosphine imide in ethyl ether and characterized crystallographically. In ether solution, a dynamic equilibrium exists between the chelated pentacoordinated and unchelated tetra-coordinated silicon moieties. Reaction of the pentacoordinated derivative with water gives [2-(diphenylphosphino)phenyl]diphenylsilanol accompanied by both reduction of the phosphine imide moiety and the hydrolytic oxidation of the Si-H moiety." °... 

Another ligand including a thiophene moiety but lacking the C2-symmetry and thus bearing electronically different phosphorus atoms was prepared by these authors, in 2001. The electrochemical oxidative potential was obtained by cyclic voltammetry. The oxidation potential of the phosphine group located on the phenyl ring was found to be 0.74 V (vs. Ag/Ag" ) and the authors attributed a value of 0.91 V to the phosphine attached to the thiophene moiety. This second functionality is a rather electron-poor phosphine. As shown... 

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