Synthese des complexes de rh, cr et w contenant le coordinat diazo en faisant reagir les sels de ... more Synthese des complexes de rh, cr et w contenant le coordinat diazo en faisant reagir les sels de li des anions rc(n::(2))**(-) sur les complexes metalliques. On a isole: (pme::(3))::(4) rhc(n::(2))sime::(3) (pet::(3))::(3) rhc(n::(2))sime::(3), (pme::(3))::(2) rhc(n::(2))(s)p(n-ipr::(2))::(2). On a mis en evidence un complexe carbenique dimere possedant un groupe ylure, lors de la photolyse de (pet::(3))::(3) rhc(n::(2))sime::(3)
The reactions of some substituted 2,8-dioxabicyclo[3.2.1]oct-3-ylmethanols (hydroxy acetals) with... more The reactions of some substituted 2,8-dioxabicyclo[3.2.1]oct-3-ylmethanols (hydroxy acetals) with oxalic acid in aqueous methanol solution gave tetrahydrofurans stereospecifically in good yields.The reactions occur with inversion of configuration at a tertiary carbon and are considered to proceed by a mechanism involving the carbonyl group generated by hydrolysis of the acetal function.
... 4 (a) MJ Menu, P. Desrosiers, M. Dartiguenave, Y. Dartiguenave and G. Bertrand, Organometalli... more ... 4 (a) MJ Menu, P. Desrosiers, M. Dartiguenave, Y. Dartiguenave and G. Bertrand, Organometallics, 6 (1987) 1822; (b) MJ Menu, E. Deydier, M. Dartiguenave, Y. Dartiguenave, AL Beauchamp, J. Brewer and HB Gray, unpublished. ...
The reaction of 2-[3-(triethoxysilyl)propylamino]ethanethiol (LH, a) and 1-methyl-2-[3-(triethoxy... more The reaction of 2-[3-(triethoxysilyl)propylamino]ethanethiol (LH, a) and 1-methyl-2-[3-(triethoxysilyl)propylamino]ethanethiol (LH, b) with ZnX2 and CdX2 (X = Cl, Br, I, NO3) in tetrahydrofuran (THF) or CH2Cl2 gives several complexes depending on the experimental conditions. Elemental analyses, IR, Raman, 13C[1H], 1H NMR and mass spectroscopies indicated the formation of mononuclear and dinuclear complexes. In the absence of NEt3 as proton quencher, the protonated ligands react in their zwitterionic form giving dinuclear [M(LH)X2]2 [M = Zn (1), Cd (2); LH = a, b; X = Cl, Br, I] or mononuclear M(NO3)2(LH)2 [M = Zn (5), Cd (6); LH = a] complexes. In both cases, coordination occurs through the S atoms, the ligands acting as terminal and bridging species. With NEt3, the deprotonated ligands are chelated through their N and S atoms and bridging occurs through the S atoms in [MLX]2 [M = Zn (3), Cd (4); LH = a; X = Cl, Br] complexes. The LH ligand is chemically grafted onto silica, the procedure optimized and the resulting material characterized by 13C and 29Si cross-polarization, magic-angle spinning (CP-MAS) NMR and DRIFT. This material is evaluated as a supported molecular trap for binding heavy metals (Cd2+, Hg2+, Pb2+) in aqueous solution. In both batch and column processes, it appears that Hg2+ and Pb2+ are trapped more than Cd2+, but in all cases values lower than those allowed were obtained.
ABSTRACT Molecular (N,S) aminothiols R(CH2)3NH(CH2)2SH (1), R(CH2)3NH(CH2CHMe)SH (2), R(CH2)3NH(C... more ABSTRACT Molecular (N,S) aminothiols R(CH2)3NH(CH2)2SH (1), R(CH2)3NH(CH2CHMe)SH (2), R(CH2)3NH(CH2)2S(CH2)2SH (3), R(CH2)3NH(CH2CHMe)S(CH2CHMe)SH (4) and R(CH2)3N[(CH2)2SH]2 (5) [R=(EtO)3Si] have been prepared by a one step reaction of olefin sulfide on aminopropyltriethoxysilane and characterised by physicochemical methods; the grafting of 1 on silica is reported.
We compared mercaptopropyl fonctionalized silica, =SiSH, with two aminoethanethiol modified silic... more We compared mercaptopropyl fonctionalized silica, =SiSH, with two aminoethanethiol modified silica gels, =SiNS and =SiNMeS, for their ability to remove Cd 2+ and Pb 2+ from aqueous solutions. Adsorption was performed using a batchwise process. The maximum adsorption capacities were obtained for lead and cadmium. The adsorption isotherms followed the Langmuir model. The calculated parameters indicated a similar removal capacity
Synthese des complexes de rh, cr et w contenant le coordinat diazo en faisant reagir les sels de ... more Synthese des complexes de rh, cr et w contenant le coordinat diazo en faisant reagir les sels de li des anions rc(n::(2))**(-) sur les complexes metalliques. On a isole: (pme::(3))::(4) rhc(n::(2))sime::(3) (pet::(3))::(3) rhc(n::(2))sime::(3), (pme::(3))::(2) rhc(n::(2))(s)p(n-ipr::(2))::(2). On a mis en evidence un complexe carbenique dimere possedant un groupe ylure, lors de la photolyse de (pet::(3))::(3) rhc(n::(2))sime::(3)
The reactions of some substituted 2,8-dioxabicyclo[3.2.1]oct-3-ylmethanols (hydroxy acetals) with... more The reactions of some substituted 2,8-dioxabicyclo[3.2.1]oct-3-ylmethanols (hydroxy acetals) with oxalic acid in aqueous methanol solution gave tetrahydrofurans stereospecifically in good yields.The reactions occur with inversion of configuration at a tertiary carbon and are considered to proceed by a mechanism involving the carbonyl group generated by hydrolysis of the acetal function.
... 4 (a) MJ Menu, P. Desrosiers, M. Dartiguenave, Y. Dartiguenave and G. Bertrand, Organometalli... more ... 4 (a) MJ Menu, P. Desrosiers, M. Dartiguenave, Y. Dartiguenave and G. Bertrand, Organometallics, 6 (1987) 1822; (b) MJ Menu, E. Deydier, M. Dartiguenave, Y. Dartiguenave, AL Beauchamp, J. Brewer and HB Gray, unpublished. ...
The reaction of 2-[3-(triethoxysilyl)propylamino]ethanethiol (LH, a) and 1-methyl-2-[3-(triethoxy... more The reaction of 2-[3-(triethoxysilyl)propylamino]ethanethiol (LH, a) and 1-methyl-2-[3-(triethoxysilyl)propylamino]ethanethiol (LH, b) with ZnX2 and CdX2 (X = Cl, Br, I, NO3) in tetrahydrofuran (THF) or CH2Cl2 gives several complexes depending on the experimental conditions. Elemental analyses, IR, Raman, 13C[1H], 1H NMR and mass spectroscopies indicated the formation of mononuclear and dinuclear complexes. In the absence of NEt3 as proton quencher, the protonated ligands react in their zwitterionic form giving dinuclear [M(LH)X2]2 [M = Zn (1), Cd (2); LH = a, b; X = Cl, Br, I] or mononuclear M(NO3)2(LH)2 [M = Zn (5), Cd (6); LH = a] complexes. In both cases, coordination occurs through the S atoms, the ligands acting as terminal and bridging species. With NEt3, the deprotonated ligands are chelated through their N and S atoms and bridging occurs through the S atoms in [MLX]2 [M = Zn (3), Cd (4); LH = a; X = Cl, Br] complexes. The LH ligand is chemically grafted onto silica, the procedure optimized and the resulting material characterized by 13C and 29Si cross-polarization, magic-angle spinning (CP-MAS) NMR and DRIFT. This material is evaluated as a supported molecular trap for binding heavy metals (Cd2+, Hg2+, Pb2+) in aqueous solution. In both batch and column processes, it appears that Hg2+ and Pb2+ are trapped more than Cd2+, but in all cases values lower than those allowed were obtained.
ABSTRACT Molecular (N,S) aminothiols R(CH2)3NH(CH2)2SH (1), R(CH2)3NH(CH2CHMe)SH (2), R(CH2)3NH(C... more ABSTRACT Molecular (N,S) aminothiols R(CH2)3NH(CH2)2SH (1), R(CH2)3NH(CH2CHMe)SH (2), R(CH2)3NH(CH2)2S(CH2)2SH (3), R(CH2)3NH(CH2CHMe)S(CH2CHMe)SH (4) and R(CH2)3N[(CH2)2SH]2 (5) [R=(EtO)3Si] have been prepared by a one step reaction of olefin sulfide on aminopropyltriethoxysilane and characterised by physicochemical methods; the grafting of 1 on silica is reported.
We compared mercaptopropyl fonctionalized silica, =SiSH, with two aminoethanethiol modified silic... more We compared mercaptopropyl fonctionalized silica, =SiSH, with two aminoethanethiol modified silica gels, =SiNS and =SiNMeS, for their ability to remove Cd 2+ and Pb 2+ from aqueous solutions. Adsorption was performed using a batchwise process. The maximum adsorption capacities were obtained for lead and cadmium. The adsorption isotherms followed the Langmuir model. The calculated parameters indicated a similar removal capacity
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