Synthesis, Crystal Structures, and Optical and Magnetic Properties of Samarium, Terbium, and Erbium Coordination Entities Containing Mono-Substituted Imine Silsesquioxane Ligands.

Mono-substituted cage-like silsesquioxanes of the T-type can play the role of potential ligands in the coordination chemistry. In this paper, we report on imine derivatives as ligands for samarium, terbium, and erbium cations and discuss their efficient synthesis, crystal structures, and magnetic and optical properties. X-ray analysis of the lanthanide coordination entities [MCl(POSS)]·2THF [M = Er (), Tb (), Sm ()] showed that all three compounds crystallize in the same space group with similar lattice parameters.

Heterometallic 3d-4f Alkoxide Precursors for the Synthesis of Binary Oxide Nanomaterials.

In this study, a new method for the synthesis of heterometallic 3d-4f alkoxides by the direct reaction of metallic lanthanides (La, Pr, Nd, Gd) with MCl (M = Mn, Ni, Co) in 2-methoxyethanol was developed. The method was applied to the synthesis of the heterometallic oxo-alkoxide clusters [LnMn(μ-O)(μ-OR)(HOR)Cl] (Ln = La (), Nd (), Gd (); = 0, 2, 4); [PrM(μ-O)(μ-OR)(HOR)Cl] (M = Co (), Ni (); = 2, 4); and [LnMn(μ-OH)(μ-OR)(μ-OR)(μ-Cl)(HOR)Cl] (Ln = La () and Pr ()). Mechanistic investigation led to the isolation of the homo- and heterometallic intermediates [Pr(μ-OR)(μ-Cl)(HOR)Cl] (), [Co(μ-OR)(HOR)Cl] (), [Ni(μ-OR)(HOEt)Cl] (), [Mn(μ-OR)(HOR)(HOEt)Cl] (), and [Nd(HOR)Cl][CoCl] ().

Use of group 13 aryloxides for the synthesis of green chemicals and oxide materials.

In this work, group 13 metal aryloxides [Al(MesalO)] (1), [MeGa(MesalO)] (2), [AlLi(MesalO)] (3) and [MeGaLi(MesalO)(THF)] (4) were obtained by the reaction of methyl salicylate (MesalOH) with group-13 alkyls MMe (for M = Al, Ga) or their combination with BuLi in a THF/alcohol solution. The direct reaction of MMe (for M = Al, Ga) and MesalOH (1 : 3) led to compound 1 or 2, respectively. When the same reactions were carried out with additional BuLi, the heterometallic compound 3 or the mixture of 4 and [Li(MesalO)] (5) was obtained.

Synthesis, Crystal Structures, and Spectroscopic Properties of Novel Gadolinium and Erbium Triphenylsiloxide Coordination Entities.

In alkali metal and lanthanide coordination chemistry, triphenylsiloxides seem to be unduly underappreciated ligands. This is as surprising as that such substituents play a crucial role, among others, in stabilizing rare oxidation states of lanthanide ions, taking a part of intramolecular and molecular interactions stabilizing metal-oxygen cores and many others. This paper reports the synthesis and characterization of new lithium [Li(OSiPh)(THF)] (), and sodium [Na(OSiPh)] () species, which were later used in obtaining novel gadolinium [Gd(OSiPh)(THF)]·THF (), and erbium [Er(OSiPh)(THF)]·THF () configuration, it can result in res were determined for all - compounds, and in addition, IR, Raman, absorption spectroscopy studies were conducted for and lanthanide compounds.

Polyoxometalate-like structure of new potassium triphenylsiloxides: [K(OSiPh)(CHOH)(HO)]·2CHCH and [K(OSiPh)(HO)].

The synthesis and structural characterization of two new potassium triphenylsiloxides, namely, aqua(propan-2-ol)hexakis(triphenylsilanolato)hexapotassium toluene disolvate, [K(CHOSi)(CHO)(HO)]·2CH, and diaquahexakis(triphenylsilanolato)hexapotassium, [K(CHOSi)(HO)], are reported. Both compounds crystallize in the triclinic space group P-1. The structure in each case resembles an alkali metal polyoxometalate-like structure, in which electrostatic interactions are observed in the metal-oxygen core.

Heterometallic Group 4-Lanthanide Oxo-alkoxide Precursors for Synthesis of Binary Oxide Nanomaterials.

In this study, an efficient procedure for the synthesis of uncommon group 4-lanthanide oxo-alkoxide derivatives was developed. Heterometallic clusters with the structures [LaTi(μ-O)(μ-OEt)(μ-OEt)(OEt)(Cl)(HOEt)] (), [LaZr(μ-O)(μ-OEt)(μ-Cl)(OEt)(HOEt)(Cl)] (), [LaHf(μ-O)(μ-OEt)(μ-Cl)(OEt)(HOEt)(Cl)] (), [NdTi(μ-O)(μ-OEt)(μ-OEt)(OEt)(HOEt)(Cl)] (), [NdZr(μ-O)(μ-OEt)(μ-Cl)(OEt)(HOEt)(Cl)] (), and [NdHf(μ-O)(μ-OEt)(μ-Cl)(OEt)(HOEt)(Cl)] () were synthesized via the reaction of a metallocene dichloride, CpM'Cl (where M' = Ti, Zr, and Hf), and metallic lanthanum or neodymium in the presence of excess ethanol. This procedure gave crystalline precursors with molecular stoichiometries suitable for obtaining group 4-lanthanide oxide materials.

Convenient Route to Heterometallic Group 4-Zinc Precursors for Binary Oxide Nanomaterials.

In this study, simple and efficient synthetic routes to a family of uncommon group 4-zinc heterometallic alkoxides were developed. Single-source molecular precursors with the structures [CpTiZn(μ,η-OR)(THF)Cl] (), [ZrZn(μ-O)(μ,η-OR)(μ-OH)(μ,η-OR)(μ,η-OR)Cl] (), and [HfZn(μ-O)(μ,η-OR)(μ-OH)(μ,η-OR)(μ,η-OR)Cl] () were prepared via reduction of CpTiCl with metallic zinc or protonolysis of the metal-cyclopentadienyl bond in CpM'Cl (M' = Zr or Hf) in the presence of 2-methoxyethanol (ROH) and Zn(OR). This synthetic route enables the creation of compounds with well-defined molecular structures and therefore provides precursors suitable for obtaining group 4-zinc oxides.

Molecular Routes to Group IV Magnesium and Calcium Nanocrystalline Ceramics.

The effect of alkaline-earth-metal alkoxides on the protonolysis of CpM'Cl (M' = Ti, Zr, Hf; Cp = cyclopentadiene) was investigated. This approach enabled the design of compounds with well-defined molecular structures to generate high-purity binary metal oxides. Single-source molecular precursors with structures of [MM'(μ-OEt)(μ-OEt)(OEt)(EtOH)] with M = Mg and M' = Ti (1), Zr (2), and Hf (3), [CaTi(μ-O)(μ-O)(μ-OEt)(OEt)(EtOH)Cl] (4), and [MM'(μ-O)(μ-OEt)(OEt)(EtOH)Cl] with M = Ca and M' = Zr (5) and Hf (6) were prepared via elimination of the cyclopentadienyl ring from CpM'Cl as CpH in the presence of M(OEt) and ethanol (EtOH) as a source of protons.

Impact of Group 13 Metals on CpTiCl Reduction and Structural Characterization of Resulting Compounds.

The aim of the current study was to examine the effects of group 13 metals on CpTiCl reduction in the presence of 2-methoxyethanol (MeOEtOH) or ethanol (EtOH) and the compositions of the resulting products. Direct reaction of CpTiCl and M [Al, Al (Fe contaminated), Ga, In] in toluene/alcohol for 2 h gave a new family of uncommon homo- and heterometallic compounds: [CpTiAl(μ,η-OEtOMe)Cl][Ti(μ,η-OEtOMe)(η-OEtOMe)Cl] (1), [CpTiAl(μ,η-OEtOMe)Cl]Cl (2), [CpTiAl(μ,η-OEtOMe)Cl][CpTi(η-HOEtOMe)][FeCl] (3), [CpTi(η-HOEtOMe)][GaCl][Cl] (4), [CpTi(μ-OEt)(OEt)][GaCl] (5), [CpTi(μ,η-OEtOMe)Cl] (6), and [CpTi(μ,η-OEtOMe)(μ-OEtOMe)Cl] (7). The reaction with indium for 48 h resulted in isolation of [TiIn(μ,η-OEtOMe)(OEtOMe)Cl] (8), [In(μ-OEtOMe)(HOEtOMe)Cl] (9), and [Ti(OEtOMe)] (10).

Unexpected Reactions between Ziegler-Natta Catalyst Components and Structural Characterization of Resulting Intermediates.

In this work, we investigated precursors and procatalysts with well-defined crystal structures and morphologies in Ziegler-Natta systems to improve our understanding of the nature of the active metal sites. Molecular cluster precursors such as [Mg4Ti3(μ6-O)(μ3-OH)3(μ-OEt)9(OEt)3(EtOH)3Cl3], [Mg4Ti3(μ6-O)(μ3-OH)(μ3-OEt)2(μ-OEt)9(OEt)3(EtOH)3Cl3], and [Mg6Ti4(μ6-O)2(μ3-OH)4(μ-OEt)14(OEt)4(EtOH)2Cl2] were prepared via simple elimination of the cyclopentadienyl ring from Cp2TiCl2 as CpH in the presence of magnesium metal and ethanol. Titanocene dichloride acts as both a source of titanium and a magnesium-chlorinating agent.

Crystal structure of a mixed-ligand dinuclear Ba-Zn complex with 2-meth-oxy-ethanol having tri-phenyl-acetate and chloride bridges.

The dinuclear barium-zinc complex, μ-chlorido-1:2κ(2) Cl:Cl-chlorido-2κCl-bis-(2-meth-oxy-ethanol-1κO)bis-(2-meth-oxy-ethanol-1κ(2) O,O')bis-(μ-tri-phenyl-acetato-1:2κ(2) O:O')bariumzinc, [BaZn(C20H15O2)2Cl2(C3H8O2)4], has been synthesized by the reaction of barium tri-phenyl-acetate, anhydrous zinc chloride and 2-meth-oxy-ethanol in the presence of toluene. The barium and zinc metal cations in the dinuclear complex are linked via one chloride anion and carboxyl-ate O atoms of the tri-phenyl-acetate ligands, giving a Ba⋯Zn separation of 3.9335 (11) Å.

Transformation of barium-titanium chloro-alkoxide compound to BaTiO3 nanoparticles by BaCl2 elimination.

In this Article, we present how the molecular precursor of binary oxide material having an excess of alkali earth metal can be transformed to the highly phase pure BaTiO3 perovskite. Here, we synthesized and compared two barium-titanium complexes with and without chloride ligands to determine the influences of different ligands on the phase purity of binary oxide nanoparticles. We prepared two barium-titanium complexes, i.

Design of a magnesium-pridinolum complex for polylactide-drug conjugates formation.

Polylactide conjugates of the muscle contraction agent Pridinolum (PriOH = 1,1-diphenyl-3-(1-piperidinyl)-1-propanol) were prepared directly by ring-opening polymerization of L-lactide (L-LA) mediated by the pridinolum magnesium complex [Mg(μ,η(2)-OPri)(η(1)-OPri)](2). The ancillary O,N - bifunctional drug as a ligand stabilizes the magnesium species and initiates L-LA polymerization affording a polymer chain terminated by covalently attached drug molecules to the PLLA through ester linkers to form PriO-PLLA conjugate. Up to 80% of the pridinolum can be released from the conjugate by treatment with deuterated hydrochloric acid DCl at pH = 1.

Titanocene as a precursor for a cyclopentadienyl-free titanium(III)-manganese(II) cluster: a new approach for nano-size materials.

A simple and unique route to access the heterometallic cluster [Mn4Ti4(micro-Cl)2(micro3,eta2-L)2(micro,eta2-L)10Cl6] (1) with two Mn2Ti2 butterfly core motifs is reported. This method comprises elimination of the Cp ring from Cp2TiCl2 as CpH in the presence of metallic Mn in 2-methoxoethanol (LH) as a proton source. Complex 1 belongs to a group of magnetic clusters, which consists of two weakly interacting M4 subunits.

Cyclopentadienyl/alkoxo ligand exchange in group 4 metallocenes: a convenient route to heterometallic species.

A simple and efficient strategy for the synthesis of nonorganometallic heterometallic clusters from cheap organometallic precursors is reported. This unique synthetic method involves elimination of the cyclopentadienyl ring from Cp(2)MCl(2) (M = Ti, Zr, Hf) as CpH in the presence of M'L(2) or M'L'(2) (M' = Ca, Sr, Mn; CH(3)OCH(2)CH(2)OH = LH or (CH(3))(2)NCH(2)CH(2)OH = L'H) in an alcohol as a source of protons. In the reactions presented, a series of compounds, [Ca(4)Ti(2)(mu(6)-O)(mu(3),eta(2)-L)(8)(eta-L)(2)Cl(4)] (1), [Sr(4)Hf(2)(mu(6)-O)(mu(3),eta(2)-L)(8)(eta-L)(2)(eta-LH)(4)Cl(4)] (2), [Ca(4)Zr(2)(mu(6)-O)(mu-Cl)(4)(mu,eta(2)-L)(8)Cl(2)] (3), [Sr(4)Ti(2)(mu(6)-O)(mu(3),eta(2)-L)(8)(eta-L)(2)(eta-LH)(2)Cl(4)] (4), [Ca(4)Zr(2)Cp(2)(mu(4)-Cl)(mu-Cl)(3)(mu(3),eta(2)-L)(4)(mu,eta(2)-L)(4)Cl(2)] (5), [CaTiCl(2)(mu,eta(2)-L')(3)(eta-L'H)(3)][L'] (6), [Ca(2)Ti(mu,eta(2)-L')(6)Cl(2)] (7), [Mn(4)Ti(4)(mu-Cl)(2)(mu(3),eta(2)-L)(2)(mu,eta(2)-L)(10)Cl(6)] (8), and [Mn(10)Zr(10)(mu(4)-O)(10)(mu(3)-O)(4)(mu(3),eta(2)-L)(2)(mu,eta(2)-L)(16)(mu,eta-L)(4)(eta-L)(2)Cl(8)] (9), were obtained in good yield.

Unexpected cyclopentadienyl/alkoxo ligand exchange in titano- and zirconocene. New opportunities.

A simple new route to access heterometallic alkoxo precursors for a wide range of materials is reported. This unique synthetic method comprises elimination of the cyclopentadienyl ring from Cp2MCl2 (M = Ti, Zr) as CpH in the presence of M'(OR)2 (M' = Ca, Mn; OR = OCH2CH2OCH3 or OEt) in an alcohol as a source of protons. In one-pot reactions, we have prepared four different compounds with Ti2Ca4(mu6-O), Cp2Zr2Ca4(mu4-Cl), Zr10Mn10(mu3-O) 14, and Cp3Ti2(mu-OEt)2 motifs.

cis-Dichloridobis[2-(hydroxy-meth-yl)tetra-hydro-furan-κO,O']manganese(II).

The structure of the title compound, [MnCl(2)(C(5)H(10)O(2))(2)], was solved from low-temperature data collected at 100 (2) K. The asymmetric unit contains one half-mol-ecule with the Mn(II) ion located on a twofold axis. A distorted octa-hedral environment around the Mn atom is formed by two ether and two hydroxyl O atoms of two 2-(hydroxy-methyl)tetra-hydro-furan ligands, and by two chloride ions.

A pentanuclear bimetallic complex of manganese(II) and aluminium(III) ions: tetra-mu2-iodido-iodidobis(mu3-2-methoxyethanolato)bis(mu2-2-methoxyethanolato)dimethyl(tetrahydrofuran-kappaO)aluminium(III)tetramanganese(II).

The molecule of the title compound, [Mn(4)Al(CH(3))(2)(C(3)H(7)O(2))(4)I(5)(C(4)H(8)O)], contains one Al(III) and four Mn(II) ions. Two Mn atoms are five-coordinate in the form of a trigonal bipyramid or a square pyramid. The two other Mn atoms are six-coordinate with an octahedral geometry.

Titanium-manganese compound with a chiral Mn3Ti center.

We have shown here for the first time a facile route to the molecular compound [Mn3Ti(mu3-OCH2CH2OCH3)2(mu-OCH2CH2OCH3)3(mu-Cl)Cl2(OiPr)2] with a Mn3Ti motif, where the Ti atom is in the chiral position and the Mn atoms occupy nonchiral sites.

Syntheses, structure, and properties of a manganese-calcium cluster containing a Mn4Ca2 core.

We describe here a novel, simple, efficient self-assembly method for the in situ generation of [Mn4Cl4(micro-OCH2CH2OMe)4(EtOH)4] and [Mn4(micro-Cl)Cl3(micro-OCH2CH2OMe)4(HOCH2CH2OMe)3]2 cubane-type compounds which react readily with calcium species to form cluster [Mn4Ca2Cl4(micro-OCH2CH2OMe)8], the calcium atoms attached to the Mn4 unit of flatten out the cubane inducing significant conformational changes.

Deoligomerization by cocomplexation: syntheses and structures of aluminum-calcium alkoxides and aryloxides.

Reactions of oligomeric "Ca(dbbfo)2" and Ca9(CH3OCH2CH2O)18(CH3OCH2CH2OH)2 with Al(CH3)3 in toluene gave tetranuclear heterobimetallic [Ca(mu-dbbfo){(mu-dbbfo)(mu-CH3)Al(CH3)2}]2 (71%) and polymeric Ca{(mu-CH3OCH2CH2O)(mu-CH3)Al(CH3)2}2 (86%). The latter can be obtained as monomeric THF adduct Ca{(mu-CH3OCH2CH2O)Al(CH3)3}2(THF)2 (78%) when a mixture of solvents is used. The results, including an initial L-lactide polymerization test, are discussed in the context of calcium alkoxo cluster degradation in solution.

Structural characterization of a methylaluminoxane (MAO)-magnesium dichloride cluster: model of MAO grafted onto a MgCl2 support.

The study outlines our initial results that contribute to a better understanding of MAO/MgCl2 (MAO=methylaluminoxane) incorporation in the Cp2ZrCl2/MAO/MgCl2 catalytic system, which is currently of global industrial use. We show here that the[Al3(mu3-O)(Me)5]2+ moiety can be trapped by the tetrapodal [Mg3Cl4(thffo)4(THF)]2- macrounit to form a cluster [Al3Mg3(mu3-O)(thffo)4(Me)5Cl4(THF)] (thffo=2-tetrahydrofurfuroxide). From this perspective, this macrounit might be considered as a part of the MgCl2 support surface, which fulfills the requirement of a Al3(mu3-O) core.

Synthesis of homoleptic barium alkoxides and aryloxides and their reactions with Al(CH(3))(3): a convenient route to heterometallic species.

Reactions of metallic Ba with benzofuranol (dbbfoH) or diethylene glycol give homoleptic and homonuclear complexes Ba(dbbfo)(2)(dbbfoH)(2).3dbbfoH and Ba{O(CH(2)CH(2)O)(2)}{O(CH(2)CH(2)OH)(2)}(2) (60-89%). Both compounds and formerly described Ba{O(CH(2)CH(2)O)(2)Me}(2) react with Al(CH(3))(3) to yield trinuclear heterobimetallic low-coordinated barium compounds with structure and geometry depending on the reaction stoichiometry and crystallization procedure.

The first structurally characterized nonorganometallic titanium(III) alkoxo-bridged dinuclear complexes.

The reaction of [Ti4(OMe)14Cl2] (1) with an excess of AlMe3 gave the cocrystallite [Ti2(mu-OMe)2(mu-Cl)Cl3(thf)3].[Ti2(mu-OMe)3Cl3(thf)3] (2.3) species in a 1:1 ratio.

A family of Group 4 metal alkoxo complexes with an M3(mu3-O) core relevant to Ziegler-Natta catalyst intermediates.

Reactions of [Mg(thffo)(2)] (1) or [Ca(thffo)(2)] (2) with ZrCl(4) or HfCl(4) in a CH(2)Cl(2)/THF/CH(3)CN mixture give thermally stable neutral heterobimetallic tetranuclear complexes [M(3)M'(mu(x)-O)(mu,eta(2)-thffo)(6)(Cl)(6)] (thffo=tetrahydrofurfuroxide; M/M'/x: 3, Zr/Mg/3; 4, Hf/Mg/3; 5, Zr/Ca/4; 6, Hf/Ca/4) as colorless crystals in 75-82 % yield. X-ray diffraction studies show complexes 3-5 to contain oxo-bridged M(3) triangles that are capped by an alkaline earth metal-containing moiety to form species of C(3) symmetry. Reactions of ZrCl(4) and HfCl(4) with pure tetrahydrofurfuryl alcohol in EtOH and MeOH provide ionic complexes [M(3)(mu(3)-O)(mu,eta(2)-thffo)(3)(L)(3)(Cl)(6)]Cl (M/L: 8, Zr/EtOH; 9, Hf/EtOH; 10, Zr/MeOH) in 66-79 % yield.