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Tetrafluoroborate Salts (tetrafluoroborate + salt)
Kinds of Tetrafluoroborate Salts Selected Abstractsendo and exo Coordination of Indanol: Synthesis, Isolation and Structural Characterisation of [H3Ru3(endo -Indanol)(C6Me6)2(O)]+ and [H3Ru3(exo -Indanol)(C6Me6)2(O)]+ as Their Tetrafluoroborate SaltsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2004Ludovic Vieille-Petit Abstract The reaction of 2,3,4,7-tetrahydro-1H -inden-2-ol with ruthenium chloride hydrate in refluxing ethanol yields the chloro-bridged dinuclear complex [RuCl2(indanol)]2 (1). The mononuclear complex [Ru(indanol)(H2O)3]2+ (2), formed in situ from 1 in aqueous solution, reacts with the dinuclear complex [H3Ru2(C6Me6)2]+ to give a trinuclear arene-ruthenium cluster as a mixture of two isomers, the cations [H3Ru3(endo -indanol)(C6Me6)2(O)]+ (3a) and [H3Ru3(exo -indanol)(C6Me6)2(O)]+ (3b), in a 1:1 ratio. The hydroxy function of the indanol ligand is oriented towards the ,3 -oxo cap of 3a, whereas the OH group is bent away from the metal skeleton of 3b. These two isomers, which can easily be separated by silica-gel chromatography, were isolated and characterised as their tetrafluoroborate salts. The single-crystal X-ray structure analysis of [3a][BF4] shows a strong intramolecular hydrogen bond between the ,3 -oxo ligand and the hydroxyl function, which even persists in acetone solution, as demonstrated by NMR spectroscopy. On the other hand, the hydroxy function of 3b was found to be free in the solid state as well as in solution, as shown by an X-ray crystal structure analysis and by NMR spectroscopy. The catalytic activities of the water-soluble trinuclear cations 3a and 3b for the hydrogenation of benzene to give cyclohexane under biphasic conditions are considerably different, the exo isomer 3b being more active than the endo isomer 3a. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Efficient and Practical Cross-Coupling of Arenediazonium Tetrafluoroborate Salts with Boronic Acids Catalyzed by Palladium(0)/Barium CarbonateADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2008François-Xavier Felpin Abstract The cross-coupling reaction of arenediazonium tetrafluoroborate salts with boronic acids catalyzed by the unusual palladium(0)/barium carbonate catalyst is described as an extremely practical and highly efficient alternative to classical homogeneous conditions. Reactions are conducted under mild conditions at room temperature without any base and ligand. The opportunity of preparing unsymmetrical terphenyls in a one-pot process is also demonstrated. Finally, the power of this methodology is highlighted by the synthesis of Bifenazate. [source] ChemInform Abstract: Efficient and Practical Cross-Coupling of Arenediazonium Tetrafluoroborate Salts with Boronic Acids Catalyzed by Palladium(0)/Barium Carbonate.CHEMINFORM, Issue 32 2008Francois-Xavier Felpin Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Palladium Catalyzed Heck Reaction of Arenediazonium Tetrafluoroborate Salts with Baylis,Hillman Adducts: Production of ,-Benzyl-,-keto Esters.CHEMINFORM, Issue 22 2006Rolando Perez Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Water-Soluble Arene Ruthenium Complexes Containing a trans -1,2-Diaminocyclohexane Ligand as Enantioselective Transfer Hydrogenation Catalysts in Aqueous SolutionEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 22 2005Jérôme Canivet Abstract The cationic chloro complexes [(arene)Ru(H2N,NH2)Cl]+ (1: arene = C6H6; 2: arene = p -MeC6H4iPr; 3: arene = C6Me6) have been synthesised from the corresponding arene ruthenium dichloride dimers and enantiopure (R,R or S,S) trans -1,2-diaminocyclohexane (H2N,NH2) and isolated as the chloride salts. The compounds are all water-soluble and, in the case of the hexamethylbenzene derivative 3, the aqua complex formed upon hydrolysis [(C6Me6)Ru(H2N,NH2)OH2]2+ (4) could be isolated as the tetrafluoroborate salt. The molecular structures of 3 and 4 have been determined by single-crystal X-ray diffraction analyses of [(C6Me6)Ru(H2N,NH2)Cl]Cl and [(C6Me6)Ru(H2N,NH2)OH2][BF4]2. Treatment of [Ru2(arene)2Cl4] with the monotosylated trans -1,2-diaminocyclohexane derivative (TsHN,NH2) does not yield the expected cationic complexes, analogous to 1,3 but the neutral deprotonated complexes [(arene)Ru(TsN,NH2)Cl] (5: arene = C6H6; 6: arene = p -MeC6H4iPr; 7: arene = C6Me6; 8: arene = C6H5COOMe). Hydrolysis of the chloro complex 7 in aqueous solution gave, upon precipitation of silver chloride, the corresponding monocationic aqua complex [(C6Me6)Ru(TsHN,NH2)(OH2)]+ (9) which was isolated and characterised as its tetrafluoroborate salt. The enantiopure complexes 1,9 have been employed as catalysts for the transfer hydrogenation of acetophenone in aqueous solution using sodium formate and water as a hydrogen source. The best results were obtained (60 °C) with 7, giving a catalytic turnover frequency of 43 h,1 and an enantiomeric excess of 93,%. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] A Combined Experimental and Theoretical Study of Anion,, Interactions in Bis(pyrimidine) SaltsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 35 2007Angel Garcia-Raso Abstract We report the synthesis and X-ray characterization of an N,N, -tetramethylenebis(2-aminopyrimidinium) tetrafluoroborate salt that exhibits anion,, interactions that are responsible for the crystal packing. The anion forms a sandwich complex with two pyrimidine rings. When the anion is nitrate, the crystal packing is governed by anion,, interactions and hydrogen bonds, and the sandwich complex is not formed. Finally, a theoretical study of the anion,, interactions in charged pyrimidine rings is in good agreement with the experimental findings. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Highly Selective Hydrogenation of Carbon,Carbon Multiple Bonds Catalyzed by the Cation [(C6Me6)2Ru2(PPh2)H2]+: Molecular Structure of [(C6Me6)2Ru2(PPh2)(CHCHPh)H]+, a Possible Intermediate in the Case of Phenylacetylene HydrogenationCHEMISTRY - A EUROPEAN JOURNAL, Issue 1 2007Mathieu J.-L. Abstract The dinuclear cation [(C6Me6)2Ru2(PPh2)H2]+ (1) has been studied as the catalyst for the hydrogenation of carbon,carbon double and triple bonds. In particular, [1][BF4] turned out to be a highly selective hydrogenation catalyst for olefin functions in molecules also containing reducible carbonyl functions, such as acrolein, carvone, and methyljasmonate. The hypothesis of molecular catalysis by dinuclear ruthenium complexes is supported by catalyst-poisoning experiments, the absence of an induction period in the kinetics of cyclohexene hydrogenation, and the isolation and single-crystal X-ray structure analysis of the tetrafluoroborate salt of the cation [(C6Me6)2Ru2(PPh2)(CHCHPh)H]+ (2), which can be considered as an intermediate in the case of phenylacetylene hydrogenation. On the basis of these findings, a catalytic cycle is proposed which implies that substrate hydrogenation takes place at the intact diruthenium backbone, with the two ruthenium atoms acting cooperatively in the hydrogen-transfer process. [source] endo and exo Coordination of Indanol: Synthesis, Isolation and Structural Characterisation of [H3Ru3(endo -Indanol)(C6Me6)2(O)]+ and [H3Ru3(exo -Indanol)(C6Me6)2(O)]+ as Their Tetrafluoroborate SaltsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2004Ludovic Vieille-Petit Abstract The reaction of 2,3,4,7-tetrahydro-1H -inden-2-ol with ruthenium chloride hydrate in refluxing ethanol yields the chloro-bridged dinuclear complex [RuCl2(indanol)]2 (1). The mononuclear complex [Ru(indanol)(H2O)3]2+ (2), formed in situ from 1 in aqueous solution, reacts with the dinuclear complex [H3Ru2(C6Me6)2]+ to give a trinuclear arene-ruthenium cluster as a mixture of two isomers, the cations [H3Ru3(endo -indanol)(C6Me6)2(O)]+ (3a) and [H3Ru3(exo -indanol)(C6Me6)2(O)]+ (3b), in a 1:1 ratio. The hydroxy function of the indanol ligand is oriented towards the ,3 -oxo cap of 3a, whereas the OH group is bent away from the metal skeleton of 3b. These two isomers, which can easily be separated by silica-gel chromatography, were isolated and characterised as their tetrafluoroborate salts. The single-crystal X-ray structure analysis of [3a][BF4] shows a strong intramolecular hydrogen bond between the ,3 -oxo ligand and the hydroxyl function, which even persists in acetone solution, as demonstrated by NMR spectroscopy. On the other hand, the hydroxy function of 3b was found to be free in the solid state as well as in solution, as shown by an X-ray crystal structure analysis and by NMR spectroscopy. The catalytic activities of the water-soluble trinuclear cations 3a and 3b for the hydrogenation of benzene to give cyclohexane under biphasic conditions are considerably different, the exo isomer 3b being more active than the endo isomer 3a. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Efficient and Practical Cross-Coupling of Arenediazonium Tetrafluoroborate Salts with Boronic Acids Catalyzed by Palladium(0)/Barium CarbonateADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2008François-Xavier Felpin Abstract The cross-coupling reaction of arenediazonium tetrafluoroborate salts with boronic acids catalyzed by the unusual palladium(0)/barium carbonate catalyst is described as an extremely practical and highly efficient alternative to classical homogeneous conditions. Reactions are conducted under mild conditions at room temperature without any base and ligand. The opportunity of preparing unsymmetrical terphenyls in a one-pot process is also demonstrated. Finally, the power of this methodology is highlighted by the synthesis of Bifenazate. [source] | ||||||||||