Synthesis and cation-exchange properties of a bis-zwitterionic lamellar hybrid material

The synthesis of a bis-zwitterionic lamellar hybrid material containing ammonium carboxylate groups is described. Cation-exchange properties of this material towards transition metal and lanthanide ions were studied as well as the regeneration and reuse of the material.

Coordination Chemistry in the Solid: Evidence for Coordination Modes within Hybrid Materials Different from those in Solution

Two routes of incorporation of europium(III) salts into cyclam-containing hybrid materials have been explored, to elucidate the coordination mode of EuIII in cyclam-containing hybrid materials in a study of the arrangement of cyclam moieties during the solgel process. They were 1) complexation of europium salts by N-tetrasubstituted 1,4,8,11-tetraazacyclotetradecane (cyclam) derivatives bearing four hydrolysable Si(OEt)3 groups, followed by hydrolysis and polycondensation of these complexes; and 2) hydrolysis and polycondensation of N-tetrasubstituted silylated cyclam derivatives, then incorporation of europium salts directly into the hybrid materials. The coordination mode of europium salt…

X-ray crystal structures of copper(II) and cobalt(II) complexes with Schiff base ligands. Reactivity towards dioxygen

Copper(II) and cobalt(II) Schiff base complexes with derivatives of the pentadentate ligand bis(salicylideneimino-3-propyl)amine [H2salDPT] have been prepared. The X-ray crystal structures of the copper(II) complexes Cu[salDPT] and Cu[sal(n-propyltrimethylsilyl)DPT] were determined and revealed five-coordination at the metal centre in both cases. The 1 ∶ 1 dioxygen adduct of Co[sal(n-propyltrimethylsilyl)DPT] was also isolated and its X-ray molecular structure determined.

Coordination Chemistry in the Solid: Study of the Incorporation of CuII into Cyclam-Containing Hybrid Materials

Ordered mesoporous hybrid materials containing cobalt(ii) Schiff base complex

Immobilisation of Co-salen and Co-fluomine onto ordered mesoporous silica has been achieved through coordination of the cobalt to pyridine or imidazole groups covalently attached to the silica matrix. Two routes have been investigated to obtain mesoporous hybrid materials containing coordinating ligands: post synthesis grafting of 4-[2-(trimethoxysilyl)ethyl]pyridine 1 and N-trimethoxysilylpropylimidazole 2 on hexagonally ordered mesoporous silica via SiOH groups or direct synthesis method i.e. co-hydrolysis and polycondensation of the same functionalised organotrimethoxysilane with a number of equivalents of TEOS in the presence of n-hexadecylamine as structure directing agent. The first m…

Synthesis of large-pore ordered mesoporous silicas containing aminopropyl groups

Ordered mesoporous silicas with large-pore diameters incorporating aminopropyl groups in variable quantity have been synthesized via the co-condensation of tetraethyl orthosilicate (TEOS) and 3-tert-butyloxycarbonylaminopropyltriethoxysilane templated with nonionic surfactant P123 under acidic conditions. The deprotection of amino groups was then quantitatively achieved either by thermal treatment or acid hydrolysis followed by Et3N treatment, both routes leading to exactly the same materials. We showed that the free amino centers are fully accessible, by using the condensation of the amine function with benzaldehyde.

Selective Lanthanides Sequestration Based on a Self-Assembled Organosilica

International audience; In this paper, we investigate the cation-exchange properties of a self-assembled hybrid material towards trivalent ions, lanthanides (La3+,Eu3+, Gd3+,Yb3+) and Fe3+. The bis-zwitter- ionic lamellar material was prepared by sol-gel process from only 3-amino- propyltriethoxysilane (APTES), succin- ic anhydride, and ethylenediamine. In ethanol heated under reflux, the ex- change ethylenediammonium versus Ln3+ proved to be complete by com- plexometry measurements and elemen- tal analyses, one Cl ion per one LnIII remaining as expected for charge bal- ance. In aqueous solution at 20 8C, the material was found to be selective to- wards lanthanide in spite of the similar- i…