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1.
Abdallah Aissa Michel Gruselle René Thouvenot Rainer Traksmaa 《Journal of solid state chemistry》2007,180(8):2273-2278
The reaction between phenyl phosphonic dichloride (C6H5P(O)Cl2) and synthetic calcium hydroxy- and fluorapatite has been investigated. The presence of mono- or polymeric (C6H5PO) fragment bound to hydroxyapatite was evidenced by IR, and solid-state 31P NMR spectroscopy. X-ray powder analysis has shown that the apatitic structure remains unchanged during the reaction. In contrast, no reaction was found using fluorapatite. According to the results found for these two different apatites a mechanism was proposed for the formation of covalent P-O-P bonds as the result of a reaction between the C6H5P(O)Cl2 organic reagent and (HPO4)− and/or OH− ions of the hydroxyapatite. 相似文献
2.
M. Krunks I. Oja K. Tõnsuaadu M. Es-Souni M. Gruselle L. Niinistö 《Journal of Thermal Analysis and Calorimetry》2005,80(2):483-488
Thermal decomposition of dried TiO2 gel, obtained by hydrolysing acetylacetonate-modified titanium(IV) isopropoxide, was monitored by simultaneous TG/DTA/EGA-FTIR measurements in dynamic air up to 900°C. XRD and FTIR were employed to identify the solid reaction products. Thermal degradation of the TiO2 gel consists of five distinct mass loss steps, the total mass loss being 43.8%. EGA by FTIR revealed the release of H2O below 120°C; followed by acetone, isopropyl acetate and 1-propanol around 200-300°C, and finally CO and CO2 up to 550°C. Highly exothermic reaction at 410-550°C is caused by the combustion of carbon residues. Crystalline TiO2-anatase is formed around 500°C and TiO2-rutile close to 800°C. 相似文献
3.
Introduction of the propargyl dicobalt hexacarbonyl moiety onto the estradiol A ring as a potential probe in receptor studies requires protection of the ring phenolic group, and the regio-selectivity of the attack (2- versus 4-position) depends on the bulkiness of the organometallic carbenium ion. 相似文献
4.
An organometallic route for the preparation of ring-substituted 2-aryl-propanoic and -butanoic acids
This communication presents a simple and efficient way to synthesize 2-arylalkanoic acids via chromium carbonyl complexation. 相似文献
5.
Pointillart F Train C Villain F Moulin CC Gredin P Chamoreau LM Gruselle M Aullon G Alvarez S Verdaguer M 《Journal of the American Chemical Society》2007,129(5):1327-1334
Tris(bipyridine)ruthenium(II) is used as a templating agent to insert palladium(II) into three-dimensional oxalate-based networks. The templated-assembly of [Ru(bpy)(3)][Pd(2)(ox)(3)] (Pd(2)) and [Ru(bpy)(3)][PdMn(ox)(3)] (PdMn) is described. The latter compound is structurally characterized by powder X-ray diffraction and X-ray absorption spectroscopy. These techniques reveal an unusual 6-fold oxygen environment around the Pd(II) atoms with two short (2.02 Angstrom) and four long (2.17 Angstrom) Pd-O distances. As stated by magnetometry, this environment is associated with a triplet ground state (S = 1) of the palladium(II) ion: when the temperature is decreased, the chiMT product shows a monotonous decrease from 5.54 cm(3) K mol(-1) at 300 K, a value which is slightly lower than the one expected for independent paramagnetic Pd(II) (S = 1, g = 2) and Mn(II) (S = 5/2, g = 2) ions. This thermal variation is due to antiferromagnetic exchange interactions between the two spin bearers. Nevertheless, no long-range magnetic order is detected down to 2 K. These results are confirmed by an analysis of the [MII(C(2)O(4))(3)](4-) (M = Ni, Pd, Pt) complex and of a [Pd(II){mu-(C(2)O(4))Mn(II)(OH(2))(4)}(3)](2+) tetranuclear model using density functional theory. 相似文献
6.
Tõnsuaadu K Gruselle M Villain F Thouvenot R Peld M Mikli V Traksmaa R Gredin P Carrier X Salles L 《Journal of colloid and interface science》2006,304(2):283-291
The sorption mechanism of Ru3+ ions on hydroxy (HAp), carbonate (CO3HAp), and fluor apatites (FAp) has been studied in detail. Ru apatites were obtained by reaction of the apatites with RuCl3 in aqueous solution. The structure and composition of the ruthenium-modified apatites were studied by several techniques: elemental analysis, XRD, EXAFS, IR, NMR, SEM-EDS, TEM, and thermal analysis. The amount of Ru in the modified apatite varies from 7.8 to 10.5 wt% and is not related to the initial composition or the specific surface area of the apatite. The different characterization techniques show that in the Ru-modified apatites Ru is surrounded by six oxygen atoms and do not contain any chlorine. For Ru-HAp and Ru-CO3HAp the new phase is amorphous whereas it is crystalline for FAp. The catalytic oxidation ability is higher for Ru-HAp and Ru-CO3HAp compared to Ru-FAp apatite in the oxidation of benzylic alcohol. 相似文献
7.
Caspar R Cordier C Waern JB Guyard-Duhayon C Gruselle M Le Floch P Amouri H 《Inorganic chemistry》2006,45(10):4071-4078
A new family of ruthenium complexes of general formula [Ru(DIP)2(L2)]2+, where DIP = 4,7-diphenyl-1,10-phenanthroline, a bidentate ligand with an extended aromatic system, was prepared and fully characterized. When L is a monodentate ligand, the following complexes were obtained: L = CF3SO3(-1) (2), CH3CN (3), and MeOH (4). When L2 is a bidentate ligand, the compounds [Ru(DIP)2(Hcmbpy)][Cl]2 (5) and [Ru(DIP)2(H2dcbpy)][Cl]2 (6) were prepared (Hcmbpy = 4-carboxy-4'-methyl-2,2-bipyridine, H2dcbpy = 4,4'-dicarboxy-2,2'-bipyridine). Complex [Ru(DIP)2(MeOH)2][OTf]2 (4) displayed a trans configuration of the DIP ligands, which is rare for octahedral complexes featuring DIP bidentate ligands. DFT calculations carried out on 4 showed that the cis isomer is more stable by 12.2 kcal/mol relative to the trans species. The solution behaviors of monocarboxylic complex [Ru(DIP)2(Hcmbpy)][Cl]2 (5) and dicarboxylic complex [Ru(DIP)2(H2dcbpy)][Cl]2 (6) were investigated by 1H NMR spectroscopy. VT-NMR, concentration dependence, and reaction with NaOD allowed us to suggest that aggregation of the cationic species in solution, especially for 6, originates mainly from hydrogen bonding interactions. 相似文献
8.
Troitskaya L. L. Demeshchik T. V. Sokolov V. I. Mamed"yarova I. A. Malezieux B. Gruselle M. 《Russian Chemical Bulletin》2001,50(3):497-503
Trialkyl(ferrocenylmethyl)ammonium salts and their 2-substituted analogs designed for the preparation of molecular ferromagnetics based on bimetallic oxalates were synthesized using classical alkylation of dialkylaminomethylferrocenes by alkyl halides and nucleophilic substitution reaction of 2-substituted dimethylaminomethylferrocene methiodides with trialkylamines. In the case of salts with electron-donating substituents in position 2, only the latter of the two proposed routes is applicable because N-alkylation with alkyl halides is accompanied by competing ferrocenylmethylation of the starting amine. On the contrary, the salts with electron-withdrawing 2-substituents should be prepared preferably by the reaction of amines with alkyl halides, while nucleophilic trialkylamination of methiodides is complicated by deprotonation induced by bases. 相似文献
9.
Amouri H Da Silva C Malézieux B Andrés R Vaissermann J Gruselle M 《Inorganic chemistry》2000,39(22):5053-5058
A family of dicationic diyne salts of the general formula [(Co2(CO)6)2-mu,eta2,eta2-(Nu-CH2C(triple bond)C-C(triple bond)CCH2-Nu)][BF4]2 [Nu = SMe2 (3); Nu = NC6H7, 3-picoline, (5); Nu = NC9H7, quinoline (7)] were prepared and fully characterized. Three X-ray molecular structures of 3, 5, and the neutral starting material 2,4-hexadiyne-1,6-diol complex [(Co2(CO)6)2-mu,eta2,eta2-(HO-CH2C(triple bond)C-C(triple bond)CCH2-OH)] (1) are presented. Complex 1 crystallizes in the triclinic space group P1 with a = 14.722(2) A, b = 14.571(3) A, c = 14.722(2) A, alpha = 105.17(1) degrees, beta = 113.30(1) degrees, gamma = 99.20(1) degrees, and Z = 4. Complex 3 crystallizes in the monoclinic space group P2(1)/n with a = 12.758(3) A, b = 13.360(3) A, c = 20.494(3) A, beta = 91.44(1) degrees, and Z = 4, and compound 5 also crystallizes in the monoclinic space group P2(1)/n with a = 9.426(2) A, b = 21.739(5) A, c = 18.704(3) A, beta = 94.86(1) degrees, and Z = 4. The X-ray structures provide us with valuable information on the arrangement of the Co2-alkyne units, which have a cis geometry and are in sharp contrast to that observed generally for diyne-tetracobalt compounds. Complex [(Co2(CO)6)2-mu,eta2,eta2-(Me2S-CH2C(triple bond)C-C(triple bond)CCH2-SMe2)][BF4]2 (3) reacts with N-, S-, and P-centered nucleophiles and affords the related substituted complexes in high yields. The stability and reactivity of the disulfonium diyne complex 3 toward nucleophiles are compared to those of the analogous disulfonium-yne complex [(Co2(CO)6)2-mu,eta2,eta2-(Me2S-CH2-C(triple bond)C-CH2-SMe2)][BF4]2 (4). 相似文献
10.
Daniel Lefort Jacques Fossey Michel Gruselle Jean-Yves Nedelec Jeanine Sorba 《Tetrahedron》1985,41(19):4237-4252
Peracids in solution may undergo homolytic decomposition leading mostly to mixtures of acid and alcohols, these Latters being formed from either the peracid or the solvent The peracid behaves as source of radicals and also as substrate thus presenting two radicophile centers - with a nucleophilic radical (R' from peracid or S' from solvent) the site of attack is the 0-0 bond of the peracid yielding an alcohol (NuOH). The rate of this reaction increases with increasing nucleophilicity of the radical ; this reactivity is interpreted in terms of frontier orbital perturbation theory, taking into account both the orbital energy level difference and the orbital overlap.- when the radical is electrophilic, it abstracts rather the hydrogen of the peroxidic group Leading to decomposition of the peracid into acid.Hydrogen abstraction from the solvent may be also observed in appropriate cases : this process can be used for free radical hydroxylation of hydrocarbons.The relative importance of these three chain reactions in competition : 0-0 bound attack, hydrogen abstraction from the peracid and solvent transfer reaction were studied as a function of structure of the radicals, solvent properties and temperature. 相似文献