- Bis(tetramethylselenophosphoramidoyl) methylamine complexes of Cd(Ii) and Zn(Ii): Synthesis and multinuclear (31P, 77Se, and 113Cd) Nmr Characterization in solution
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Five new complexes ZnL2(ClO4)2 (1), CdL2(ClO4)2 (2), CdL2(BF4)2 (3), CdLCl2 (4), and CdL(NO3)2 (5) [L = ((Me2N)2PSe)2NMe] have been synthesized and characterized by elemental analysis, infrared (IR) and multinuclear ( 31P, 77Se, and 113Cd), and nuclear magnetic resonance (NMR) spectroscopy. The 31P and 77Se NMR data showed that the title ligand is coordinated in a bidentate fashion to the metal center via its both P=Se groups. The solution structure of the cadmium complexes was further confirmed by its 113Cd NMR spectra, which displayed a quintuplet for the perchlorate complex and a triplet for each of the nitrate and chloride complexes, respectively due to coupling with four (two ligands) and two (one ligand) equivalent phosphorus nuclei, consistent with a four-coordinate tetrahedral geometry for the cadmium center. The results are discussed and compared with the corresponding oxo and thio analogues.
- Bennis, Meriem,Alouani, Khaled
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- Bis-N,N-aminophosphine (PNP) crosslinked poly(p-tert-butyl styrene) particles: A new support for heterogeneous palladium catalysts for Suzuki coupling reactions
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Crosslinked polymer particles carrying hemilabile bis-N,N-aminophosphine (PNP) moieties are obtained by the copolymerization of a PNP-derived monomer bearing four vinyl fragments as cross-linkers, with para-tert-butylstyrene and divinylbenzene, using free radical copolymerization in presence of AIBN, performed in aqueous dispersed medium. This new support was characterized by thermogravimetric analysis, elemental analysis, laser diffraction, solid state NMR. The PNP moiety could allow monochelation to palladium. The resulting insoluble Pd-catalyst revealed to be very active for Suzuki cross-coupling with several substrates, allowing separation of the product from the catalyst by filtration. The final palladium PS-PNP catalyst could be reused for several catalytic cycles.
- Vece, Vito,Szeto, Kai C.,Charlin, Marc O.,Rouge, Pascal,De Mallmann, Aimery,Taam, Manel,Dugas, Pierre-Yves,Lansalot, Muriel,D'Agosto, Franck,Taoufik, Mostafa
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- Bis(tetraethylthiophosphoramidoyl)methylamine as an electrochemical ligand for the simultaneous detection of iron and copper bivalent cations
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A new thiophosphoramide-based electrochemical ligand was synthesized and used as a bivalent metallic cation sensor. Electrochemical studies reveal a sensitive detection process toward various cations such as Fe2+, Co2+, Ni2+, Cd2+, Cu2+ and Ca2+. The chelation process was accompanied by dramatic changes in the redox properties of the free ligand. Interestingly, the ligand shows a simultaneous sensing behavior towards iron and copper cations. The oxidation peak potentials of the two complexes can be well separated, allowing sensitive detection. Furthermore, UV–Visible spectra showed redshifts of absorbance bands of the free ligand in the presence of cations due to the coordination of the thiophosphoryl groups. Electrochemical and UV–Visible studies confirmed that the metal-ligand complexes have 1:2 stoichiometry.
- Mejri, Alma,Alouani, Khaled
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- 1,3,5-Triethylcyclotriphosph(III)azanes and Related Compounds
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The cyclophosph(III)azanes, (ClPNEt)3, Cl2P4(NEt)5, and the previously reported diphosphinoamine, Cl2P-NEt-PCl2, are formed by suitable variation of the stoichiometry of a mixture of phosphorus trichloride and ethylamine hydrochloride in refluxing sym-tetrachloroethane solution.Oxo-derivatives of the cyclic products are also formed in low yields, and in the case of (ClPNEt)3, the same oxo-derivatives can be identified as a product of the reaction with oxygen or dimethyl sulphoxide.Both (ClPNEt)3 and bicyclo-Cl2P4(NEt)5 can be converted to the analogous fluorides by reaction with antimony trifluoride.The former also gives (Cl3PNEt)2 on reaction with chlorine.Cyclotriphosph(III)azanes, (ClPNR)3 (R = Me or Et), were obtained in low yield by heating the diphosphinoamines, Cl2P-NR-PCl2.Isomeric forms of the cyclophosph(III)azanes have been distinguished by n.m.r. spectroscopy and their structures are discussed.
- Harvey, David A.,Keat, Rodney,Rycroft, David S.
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p. 425 - 432
(2007/10/02)
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- Metal complexes of fluorophosphines. 4. Reactions of mononuclear metal carbonyls with methylaminobis(difluorophosphine)
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Ultraviolet irradiation of the metal hexacarbonyls M(CO)6 (M = Cr, Mo, W) with excess CH3N(PF2)2 in diethyl ether results in complete displacement of all six carbonyl groups to give white volatile [CH3N(PF2)2]3M (M = Cr, Mo, W). Ultraviolet irradiation of Fe(CO)5 with CH3N(PF2)2 gives either yellow liquid [CH3N(PF2)2]2FeCO or orange crystalline [CH3N(PF2)2]2Fe2(CO) 5 depending upon the reaction conditions. Reaction of Fe3(CO)12 with CH3N(PF2)2 in boiling tetrahydrofuran gives yellow crystalline [CH3N(PF2)2Fe(CO)3]2 which readily loses carbon monoxide upon standing or heating in solution to form [CH3N(PF2)2]2Fe2(CO) 5. Reaction of Fe2(CO)9 with CH3N(PF2)2 at room temperature gives a mixture of yellow liquid CH3N(PF2)2[Fe(CO)4]2 and red-orange crystalline CH3N(PF2)2Fe2(CO)7. Reactions of Ni(CO)4 with CH3N(PF2)2 give white volatile insoluble {[CH3N(PF2)2]2Ni}n, colorless crystalline {[CH3N(PF2)2]3Ni}2, yellow [CH3N(PF2)2]3Ni2(CO) 2, and/or yellow [CH3N(PF2)2]2Ni2(CO) 3 depending upon the reaction conditions. The carbonyl groups in [CH3N(PF2)2]3Ni2(CO) 2 are readily replaced with a variety of ligands at room temperature even in the absence of ultraviolet irradiation to give complexes of the type [CH3N(PF2)2]3Ni2L 2 (L = (CH3O)3P, (C2H5O)3P, (C6H5)3P, monodentate CH3N(PF2)2, and (CH3)3CNC).
- King,Gimeno
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p. 2390 - 2395
(2007/10/13)
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