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Aluminum Complexes (aluminum + complex)
Selected AbstractsChemInform Abstract: Catalytic Enantioselective Pudovik Reaction of Aldehydes and Aldimines with Tethered Bis(8-quinolinato) (TBOx) Aluminum Complex.CHEMINFORM, Issue 51 2008Joshua P. Abell 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] ChemInform Abstract: Chiral Aluminum Complexes as Catalysts in Asymmetric Baeyer,Villiger Reactions of Cyclobutanones.CHEMINFORM, Issue 26 2002Carsten Bolm Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 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] Sodium Cation Migration Above the Diimine ,-System of Solvent Coordinated dpp-BIAN Sodium Aluminum Complexes (dpp-BIAN=1,2-Bis[(2,6-diisopropylphenyl)imino]acenaphthene)CHEMISTRY - A EUROPEAN JOURNAL, Issue 15 2007Herbert Schumann Prof. Abstract The reactions of the disodium salt of the 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-BIAN) ligand with one equivalent of Me2AlCl in diethyl ether, toluene, and benzene produced the complexes [Na(Et2O)2(dpp-BIAN)AlMe2] (1), [Na(,6 -C7H8)(dpp-BIAN)AlMe2] (2) and [Na(,6 -C6H6)(dpp-BIAN)AlMe2] (3), respectively. Recrystallization of 1 from hexane afforded solvent-free [{Na(dpp-BIAN)AlMe2}n] (4) or [Na(Et2O)(dpp-BIAN)AlMe2] (5) depending on the temperature of the solvent. The molecular structures of 1,5 have been determined by single-crystal X-ray diffraction. The sodium cation coordinates either one of the naphthalene rings (1) or the diimine part of the dpp-BIAN ligand (2,5). In the complexes 2 and 3, the sodium cation additionally coordinates the toluene (2) or benzene molecule (3) in an ,6 -fashion. [source] Identification and fragmentation of hydrolyzed aluminum species by electrospray ionization tandem mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 10 2004Arja Sarpola Abstract Earlier characterization of some hydrolysis products of AlCl3·6H2O was confirmed by electrospray ionization tandem mass spectrometry with increasing collision energy of projectile ions. At lower collision energies, the aqua ligands were stripped off. At higher energies, two hydroxo groups formed a bridging oxo group with loss of one water molecule. Aluminum complexes could also capture aqua ligands in the collision chamber so long as the parent ion did not fragment, and the fragment ion spectra broadened toward higher m/z values. The chloro ligands were eliminated as hydrochloric acid. The aluminum cores remained highly intact. Copyright © 2004 John Wiley & Sons, Ltd. [source] Facile Formation of Hexacyclic [Al3O2Cl] Aluminum and Alkoxide-Bridged Titanium Complexes: Reactions of AlMe3 with [Ti(L)Cl2] [L = 2,2,-Methylenebis(6- tert -butyl-4-methylphenolato)]EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2007Dao Zhang Abstract The titanium dichloride complex [(L)TiCl2] [L = 2,2,-methylenebis(6- tert- butyl-4-methylphenolato)] (1) reacted with trimethylaluminum (AlMe3) in a 1:2 ratio to give a trimetallic aluminum complex of the composition [(L)(AlMe2)3(,-Cl)] (2) with a symmetric six-membered ring [Al3(,2 -O)2(,2 -Cl)] and a four-coordinate aluminum center in the solid state. The reaction of 1 equiv. AlMe3 gave [(L)TiMeCl] (3), which could absorb O2 gas to afford the oxygen-insertion product [{(L)TiCl}2(,-OMe)2] (4) with a five-coordinate metal center. Upon reaction of H2L with AlMe3, the binuclear, four-coordinate adduct [{(L)AlMe}2] (5) was formed. Complex 4 supported on MgCl2 and activated with aluminum alkyls reveals high catalytic activity for ethylene polymerization to produce polymers with molecular weight distributions of ca. 3.1. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] N,O-chelate aluminum and zinc complexes: synthesis and catalysis in the ring-opening polymerization of ,-caprolactoneAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 1 2009Cheng Zhang Abstract Reaction between 2-(1H -pyrrol-1-yl)benzenamine and 2-hydroxybenzaldehyde or 3,5-di- tert -butyl-2-hydroxybenzaldehyde afforded 2-(4,5-dihydropyrrolo[1,2- a]quinoxalin-4-yl)phenol (HOL1NH, 1a) or 2,4-di- tert -butyl-6-(4,5-dihydropyrrolo[1,2- a]quinoxalin-4-yl)phenol (HOL2NH, 1b). Both 1a and 1b can be converted to 2-(H -pyrrolo[1,2- a]quinoxalin-4-yl)phenol (HOL3N, 2a) and 2,4-di- tert -butyl-6-(H -pyrrolo[1,2- a]quinoxalin-4-yl)phenol (HOL4N, 2b), respectively, by heating 1a and 1b in toluene. Treatment of 1b with an equivalent of AlEt3 afforded [Al(Et2)(OL2NH)] (3). Reaction of 1b with two equivalents of AlR3 (R = Me, Et) gave dinuclear aluminum complexes [(AlR2)2(OL2N)] (R = Me, 4a; R = Et, 4b). Refluxing the toluene solution of 4a and 4b, respectively, generated [Al(R2)(OL4N)] (R = Me, 5a; R = Et, 5b). Complexes 5a and 5b were also obtained either by refluxing a mixture of 1b and two equivalents of AlR3 (R = Me, Et) in toluene or by treatment of 2b with an equivalent of AlR3 (R = Me, Et). Reaction of 2a with an equivalent of AlMe3 afforded [Al(Me2)(OL3N)] (5c). Treatment of 1b with an equivalent of ZnEt2 at room temperature gave [Zn(Et)(OL2NH)] (6), while reaction of 1b with 0.5 equivalent of ZnEt2 at 40 °C afforded [Zn(OL2NH)2] (7). Reaction of 1b with two equivalents of ZnEt2 from room temperature to 60 °C yielded [Zn(Et)(OL4N)] (8). Compound 8 was also obtained either by reaction between 6 and an equivalent of ZnEt2 from room temperature to 60 °C or by treatment of 2b with an equivalent of ZnEt2 at room temperature. Reaction of 2b with 0.5 equivalent of ZnEt2 at room temperature gave [Zn(OL4N)2] (9), which was also formed by heating the toluene solution of 6. All novel compounds were characterized by NMR spectroscopy and elemental analyses. The structures of complexes 3, 5c and 6 were additionally characterized by single-crystal X-ray diffraction techniques. The catalysis of complexes 3, 4a, 5a,c, 6 and 8 toward the ring-opening polymerization of ,-caprolactone was evaluated. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||