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ABSTRACT: The reactions of LAlH(2) (L = HC(CMeNAr)(2), Ar = 2,6-iPr(2)C(6)H(3)) () with diphenylsilanediol, phenylphosphonic acid, diphenylphosphinic acid, and pyrocatechol afford compounds with the Al-O-X (X = Si, P, C) motif of composition [LAl(μ-O)](2)Si(Ph)(2) (), [LAl(μ-O)](2)PO(Ph) (), LAl[OPO(Ph)(2)](2) (), and LAl(μ-O)(2)(o-C(6)H(4)) (), respectively. Compound contains the Al-O-Si-O-Al heterotrimetallic dioxide chain. Compound features an Al(μ-O)](2)P four-membered ring, while compound exhibits a P-O-Al-O-P chain structure. Compound contains the benzo-aluminum-dioxide organic-inorganic hybrid five-membered ring. Complexes , , , and were characterized by NMR, elementary analysis, and single-crystal X-ray diffraction.
Dalton Transactions 09/2012; 41(43):13520-4. · 3.84 Impact Factor
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ABSTRACT: In the title compound, (C(28)H(43)N(2))[SnCl(3)], two pairs of molecular species are present in the asymmetric unit. The employed α-diimine opens up, forming a highly asymmetric ammonium that has its protons at one of the N atoms [N-C= 1.264 (4) and 1.516 (4) Å]. One of the C=N double bonds was oxidized to C-N, which is consistent with the bond length of 1.516 (4) Å. Meanwhile Sn(IV) was reduced to Sn(II). The (SnCl)(3) (-) anion is trigonal-pyramidal. In the crystal, mol-ecules are linked by C-H⋯Cl, N-H⋯Cl, N-H⋯N and C-H⋯N bonds. The crystal studied was twinned by pseudo-merohedry.
Acta Crystallographica Section E Structure Reports Online 06/2012; 68(Pt 6):m719-20. · 0.35 Impact Factor
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ABSTRACT: The reaction of LAlH(2) (L = HC(CMeNAr)(2), Ar = 2,6-iPr(2)C(6)H(3)) (1) with 3-methylphenylboronic acid and 3-fluorophenylboronic acid resulted in the boroxine-linked aluminum compounds LAl[OB(3-CH(3)C(6)H(4))](2)(μ-O) (2) and LAl[OB(3-FC(6)H(4))](2)(μ-O) (3), respectively. LAl[OB(2-PhC(6)H(4))(OH)](2) (4) was synthesized by the reaction of 1 with 2-biphenylboronic acid. Compound 4 is the intermediate analogue to those, which we postulated for the formation of 2 and 3. The reaction of 1 with 3-hydroxyphenylboronic acid resulted in the first metal benzoboroxole oxide LAl[OB(o-CH(2)O)C(6)H(4)](2) (5), which is formed from a compound with B-(OH)(2) and C-OH functionalities.
Inorganic Chemistry 02/2011; 50(5):2010-4. · 4.60 Impact Factor
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Chemistry 11/2010; 16(42):12530-3. · 5.93 Impact Factor
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ABSTRACT: Three β-diketiminato ligands (L1 = HC[C(Me)N(Ar)]2, Ar = 2,4,6-Me3C6H2; L2 = HC[C(Me)N(Ar)]2, Ar = 2,6-iPr2C6H3; L3 = HC[C(tBu)N(Ar)]2, Ar = 2,6-iPr2C6H3) were employed to prepare the organoaluminum hydroxides LAlR(OH) (R = Me, Et, Ph, OEt, OSiMe3) by hydrolysis of the corresponding chlorides in the presence of a N-heterocyclic carbene as HCl scavenger. Reaction of the organoaluminum hydroxide with Cp2ZrMe2 in toluene afforded the heterobimetallic oxide LAlR(μ-O)ZrMeCp2 under evolution of methane. All compounds were characterized by multinuclear NMR, IR, mass spectrometry, and elemental analysis. The structures of L1AlPh(OH) (10), L2AlPh(OH) (11), L2AlOEt(OH) (12), L2AlOSiMe3(OH) (13), and L2AlPh(μ-O)ZrMeCp2 (17) were determined by single-crystal X-ray diffraction studies. The polymerization of ethylene was studied with compound 17, which exhibits moderate catalytic activity.
01/2008;
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Berichte der deutschen chemischen Gesellschaft 09/2007; 2007(31):4919 - 4922. · 2.94 Impact Factor
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ABSTRACT: A series of novel aluminum heterobimetallic selenides were reported. The reaction of LAl(SeH)2 (1) with LiN(SiMe3)2 resulted in the formation of [LAl(SeLi)2(THF)2] (2) (L = HC(CMeNAr)2, Ar = 2,6-iPr2C6H3). Compound 2 reacted with Me2GeCl2, Ph2GeCl2, Cp2TiCl2, and Cp2ZrCl2, respectively, to produce LAl(mu-Se)2GeMe2 (3), LAl(mu-Se)2GePh2 (4), LAl(mu-Se)2TiCp2 (5), and LAl(mu-Se)2ZrCp2 (6) in moderate yields. Compounds 2-6 were characterized by elemental analysis, NMR, and electron impact-MS. The X-ray single-crystal structure of 3 is reported and confirms the spirocyclic arrangement of the aluminum atom within the six-membered AlN2C3 and four-membered AlSe2Ge rings.
Inorganic Chemistry 09/2007; 46(17):7093-6. · 4.60 Impact Factor
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ABSTRACT: The reaction of LAl (L = HC(CMeNAr)2, Ar = 2,6-iPr2C6H3) or LAlH2 with PhB(OH)2 yields the unprecedented spirocyclic LAl[(OBPh)2O] compound. The former reaction proceeds under hydrogen formation and simultaneous oxidation of the aluminum(I).
Journal of the American Chemical Society 10/2006; 128(38):12406-7. · 9.91 Impact Factor
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ABSTRACT: Three novel aluminum-containing tin(IV) heterobimetallic sulfides are reported. The reaction of [LAl(SLi)2(THF)2]2 (1) [L = HC(CMeNAr)2, Ar = 2,6-iPr2C6H3] with Ph2SnCl2, Me2SnCl2, and SnCl4 in THF respectively afforded LAl(mu-S)2SnPh2 (2), LAl(mu-S)2SnMe2 (3), and LAl(mu-S)2Sn(mu-S)2AlL (4) in moderate yields. Compounds 2, 3, and 4 were characterized by elemental analysis, NMR, electron-impact mass spectrometry, and single-crystal X-ray structural analysis.
Inorganic Chemistry 05/2006; 45(8):3312-5. · 4.60 Impact Factor
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ABSTRACT: Reactions of LAl with ethyne, mono- and disubstituted alkynes, and diyne to aluminacyclopropene LAl[eta2-C2(R1)(R2)] ((L = HC[(CMe)(NAr)]2, Ar = 2,6-iPr2C6H3); R1 = R2 = H, (1); R1 = H, R2 = Ph, (2); R1 = R2 = Me, (3); R1 = SiMe3, R2 = C[triple bond]CSiMe3, (4)) are reported. Compounds 1 and 2 were obtained in equimolar quantities of the starting materials at low temperature. The amount of C2H2 was controlled by removing an excess of C2H2 in the range from -78 to -50 degrees C. Compound 4 can be alternatively prepared by the substitution reaction of LAl[eta2-C2(SiMe3)2] with Me3SiC[triple bond]CC[triple bond]CSiMe3 or by the reductive coupling reaction of LAlI2 with potassium in the presence of Me3SiC[triple bond]CC[triple bond]CSiMe3. The reaction of LAl with excess C2H2 and PhC[triple bond]CH (<1:2) afforded the respective alkenylalkynylaluminum compounds LAl(CH=CH2)(C[triple bond]CH) (5) and LAl(CH=CHPh)(C[triple bond]CPh) (6). The reaction of LAl(eta2-C2Ph2) with C2H2 and PhC[triple bond]CH yielded LAl(CPh=CHPh)(C[triple bond]CH) (7) and LAl(CPh=CHPh)(C[triple bond]CPh) (8), respectively. Rationally, the formation of 5 (or 6) may proceed through the corresponding precursor 1 (or 2). The theoretical studies based on DFT calculations show that an interaction between the Al(I) center and the C[triple bond]C unit needs almost no activation energy. Within the AlC2 ring the computational Al-C bond order of ca. 1 suggests an Al-C sigma bond and therefore less pi electron delocalization over the AlC2 ring. The computed Al-eta2-C2 bond dissociation energies (155-82.6 kJ/mol) indicate a remarkable reactivity of aluminacyclopropene species. Finally, the 1H NMR spectroscopy monitored reaction of LAl(eta2-C2Ph2) and PhC[triple bond]CH in toluene-d8 may reveal an acetylenic hydrogen migration process.
Journal of the American Chemical Society 04/2006; 128(15):5100-8. · 9.91 Impact Factor
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Angewandte Chemie International Edition 04/2006; 45(14):2277-80. · 13.45 Impact Factor
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ABSTRACT: A series of Al(III) compounds containing the C6F5-substituted beta-diketiminate ligands LAlMeCl (2), LAlMe2 (3), LAlMeI (4), and LAlBr2 (5) (L = HC[(CMe)(NC6F5)]2) were synthesized and characterized. The hydrolysis of 2 and 4 in the presence of 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene as the hydrogen halide acceptor both lead to (LAlMe)2(mu-O) (6), a methylalumoxane derivative, which is the first hydrolysis product with the general formula of (RAlMe)(n)O. A comparison of the hydrolysis products of 2 and 4 with that of L'AlMeCl (L' = HC[(CMe)(NAr)]2, Ar = 2,6-iPr2C6H3) shows that with the C6F5-substituted beta-diketiminate ligand, it was not possible to generate LAlMe(OH). This is obviously due to the stronger Brönsted acidity of the proton and the smaller size of the C6F5 group in this compound compared to that of the corresponding 2,6-iPr2C6H3 derivative.
Inorganic Chemistry 03/2006; 45(4):1823-7. · 4.60 Impact Factor
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ABSTRACT: A series of Al(III) compounds containing the C6F5-substituted β-diketiminate ligands LAlMeCl (2), LAlMe2 (3), LAlMeI (4), and LAlBr2 (5) (L = HC[(CMe)(NC6F5)]2) were synthesized and characterized. The hydrolysis of 2 and 4 in the presence of 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene as the hydrogen halide acceptor both lead to (LAlMe)2(μ-O) (6), a methylalumoxane derivative, which is the first hydrolysis product with the general formula of (RAlMe)nO. A comparison of the hydrolysis products of 2 and 4 with that of L‘AlMeCl (L‘ = HC[(CMe)(NAr)]2, Ar = 2,6-iPr2C6H3) shows that with the C6F5-substituted β-diketiminate ligand, it was not possible to generate LAlMe(OH). This is obviously due to the stronger Brönsted acidity of the proton and the smaller size of the C6F5 group in this compound compared to that of the corresponding 2,6-iPr2C6H3 derivative.
01/2006;
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Angewandte Chemie International Edition 12/2005; 44(43):7072-4. · 13.45 Impact Factor
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ABSTRACT: Reactions between the aluminum(I) monomer LAl (L = HC[(CMe)(NAr)]2, Ar = 2,6-iPr2C6H3) and organic azides (RN3, R = C10H15 (adamantyl), Ph3Si; tBuSi(N3)3) are reported. LAl reacted with the bulky azide RN3 in toluene in a temperature range of −50 to 25 °C, resulting in the compound LAl[(NR)2N2] (R = C10H15 (1), Ph3Si (2)) instead of the expected AlN multiple bond species, while the reaction with tBuSi(N3)3 gave LAl(N3)N[(μ-Si(N3)(tBu)]2NAl(N3)L (3). Compounds 1−3 have been fully characterized by mass spectrometry and IR and multinuclear NMR spectroscopy (1H, 13C, and 29Si) as well as by single-crystal X-ray crystallography. The structural analysis of 1 and 2 reveals an AlN4 planar five-membered ring compound, suggesting a [2 + 3] cycloaddition of the AlN multiple bond species with a molecule of RN3 despite the steric bulk of the L and R substituents. Compound 3 shows a bonding of the N3 group to the Al and a formation of the N2Si2 central core, implying the migration of N3 and a [2 + 2] cycloaddition in the reaction sequence. In addition, the solvent-free reaction of an aluminum dihydride LAlH2 with ArNH2 was also investigated at elevated temperatures (150−290 °C), and a monomeric aluminum hydride amide, LAlH(NHAr) (4), was obtained as the only isolable product. The Al−H and N−H groups of 4 are shown in the IR and 1H NMR spectra. The corresponding X-ray structural analysis exhibits the Al−H and N−H bonds that are nearly arranged in position trans to the Al−NNHAr bond.
10/2005;
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Angewandte Chemie International Edition 10/2005; 44(43):7072 - 7074. · 13.45 Impact Factor
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ABSTRACT: Reaction of LK (L = HC(CMeNAr)2, Ar = 2,6-iPr2C6H3) and MnCl2(THF)1.5 in THF unexpectedly resulted in the formation of the trinuclear complex LMn(μ-Cl)2Mn(THF)2(μ-Cl)2MnL (1) in good yield. The substitution reactions of 1 with C3H5MgCl and PhCCLi, respectively, provided the monomeric LMnC3H5(THF) (2) and the dimeric [LMn(μ-CCPh)]2 (3) in moderate yield. Complexes 1−3 were characterized by single-crystal X-ray structural analysis. The structures show that compound 1 contains an ideal planar Mn3Cl4 core and a linear Mn3 trimer, the allyl ligand in 2 is in an η1 mode, and there is π-interaction between the triple bond and the metal center in 3.
08/2004;
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Inorganica Chimica Acta. 362(15):5275-5277.
