19126-89-7Relevant academic research and scientific papers
Trapping Aluminum Hydroxide Clusters with Trisilanols during Speciation in Aluminum(III)–Water Systems: Reproducible, Large Scale Access to Molecular Aluminate Models
Lokare, Kapil Shyam,Frank, Nicolas,Braun-Cula, Beatrice,Goikoetxea, Itziar,Sauer, Joachim,Limberg, Christian
supporting information, p. 12325 - 12329 (2016/10/13)
To gain molecular level insights into the properties of certain functions and units of extended oxides/hydroxides, suitable molecular model compounds are needed. As an attractive route to access such compounds the trapping of early intermediates during the hydrolysis of suitable precursor compounds with the aid of stabilizing ligands is conceivable, which was tested for the aluminum(III)/water system. Indeed, trisilanols proved suitable trapping reagents: their presence during the hydrolysis of AliBu2H in dependence on the amount of water used allowed for the isolation of tri- and octanuclear aluminum hydroxide cluster complexes [Al3(μ2-OH)3(THF)3(PhSi(OSiPh2O)3)2] (1) and [Al8(μ3-OH)2(μ2-OH)10(THF)3(p-anisylSi(OSiPh2O)3)4] (2). 1 can be regarded as the Al(OH)3cyclic trimer, where six protons have been replaced by silyl residues. While 2 features a unique [Al8(μ3-OH)2(μ2-OH)10]12+core. In contrast to most other known aggregates of this type, 1 and 2 can be readily prepared at reasonable scales, dissolve in common solvents, and retain an intact framework even in the presence of excessive amounts of water. This finding paves the way to future research addressing the reactivity of the individual functional groups.
A tripodal trisilanol ligand and its complexation behavior towards CuI, CuII, and ZnII
Schax, Fabian,Braun, Beatrice,Limberg, Christian
, p. 2124 - 2130 (2015/04/27)
A three-step synthetic route for a new tripodal branched trisilanol ligand PhSi(OSiPh2OH)3 (LH3) was developed. X-ray diffraction analysis revealed that the trisilanol crystallizes as a dimer with a cyclic hydrogen-bonding network. The reaction of LH3 with three equivalents of CunMesn (Mes = mesityl) led to a hexanuclear compound [L2Cu6] (1), which was characterized by single-crystal X-ray diffraction analysis as well as by solution NMR spectroscopy. The crystal structure of 1 revealed that the compound features a hexagonal planar CuI6 ring, which is the first of its kind in an oxygen environment. Deprotonation of the ligand with n-butyllithium and subsequent reaction with CuBr2 resulted in the dinuclear CuII complex [L′2Cu2][Li(THF2)]2 (2, THF = tetrahydrofuran), which contains a new siloxide ligand formed from L3- by the elimination of a SiOPh2 unit, as evidenced by X-ray diffraction analysis. To check if the "Ph2SiO" elimination is a general behavior of this trisilanol, the reaction with ZnBr2 was investigated under analogous conditions. However, this led to the isolation of [L2Zn2][Li(OEt)]2 (3) without any rearrangement of the siloxide ligand. A tripodal branched trisilanol ligand PhSi(OSiPh2OH)3 (LH3) was synthesized. Its reaction with three equivalents of CunMesn (Mes = mesityl) led to a hexanuclear compound [L2Cu6] with a planar CuI6 ring. Deprotonation of LH3 with n-butyllithium and subsequent reaction with either CuBr2 or ZnBr2 resulted in dinuclear complexes. In the case of CuBr2, the original ligand eliminates a "Ph2SiO" unit.
A tripodal trisilanol ligand and its complexation behavior towards Cu I, CuII, and ZnII
Schax, Fabian,Braun, Beatrice,Limberg, Christian
, p. 2124 - 2130 (2014/05/06)
A three-step synthetic route for a new tripodal branched trisilanol ligand PhSi(OSiPh2OH)3 (LH3) was developed. X-ray diffraction analysis revealed that the trisilanol crystallizes as a dimer with a cyclic hydrogen-bonding network. The reaction of LH3 with three equivalents of CunMesn (Mes = mesityl) led to a hexanuclear compound [L2Cu6] (1), which was characterized by single-crystal X-ray diffraction analysis as well as by solution NMR spectroscopy. The crystal structure of 1 revealed that the compound features a hexagonal planar CuI6 ring, which is the first of its kind in an oxygen environment. Deprotonation of the ligand with n-butyllithium and subsequent reaction with CuBr2 resulted in the dinuclear Cu II complex [L2Cu2][Li(THF2)] 2 (2, THF = tetrahydrofuran), which contains a new siloxide ligand formed from L3- by the elimination of a SiOPh2 unit, as evidenced by X-ray diffraction analysis. To check if the "Ph 2SiO" elimination is a general behavior of this trisilanol, the reaction with ZnBr2 was investigated under analogous conditions. However, this led to the isolation of [L2Zn2][Li(OEt)] 2 (3) without any rearrangement of the siloxide ligand. A tripodal branched trisilanol ligand PhSi(OSiPh2OH)3 (LH 3) was synthesized. Its reaction with three equivalents of Cu nMesn (Mes = mesityl) led to a hexanuclear compound [L2Cu6] with a planar CuI6 ring. Deprotonation of LH3 with n-butyllithium and subsequent reaction with either CuBr2 or ZnBr2 resulted in dinuclear complexes. In the case of CuBr2, the original ligand eliminates a "Ph 2SiO" unit. Copyright
