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Hiroshi Ogino - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and structure of the first dinuclear complex bridged by a substituent-free Gallium Atom
Organometallics, 2003Co-Authors: Keiji Ueno, Takahito Watanabe, Hiromi Tobita, Hiroshi OginoAbstract:The first dinuclear complex bridged by a substituent-free Gallium Atom, Cp*Fe(dppe)(μ-Ga)Fe-(CO) 4 (1; Cp* = η-C 5 Me 5 , dppe = Ph 2 PCH 2 CH 2 PPh 2 ), was synthesized by the reaction of Cp*Fe(dppe)GaCl 2 with K 2 [Fe(CO) 4 ]. A crystal structure analysis of complex 1 revealed that the geometry around the Gallium Atom is essentially linear and the Fe-Ga bonds are significantly shorter than that of usual single bonds. These structural features indicate that the Fe-Ga bonds bear significantly unsaturated character.
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synthesis of cationic diiron complexes bridged by a base stabilized Gallium Atom fp2 μ ga do2 x fp η c5h5 fe co 2 do2 2 2 bipyridine n n n n tetramethylethylenediamine 1 10 phenanthroline 4 dimethylamino pyridine 2 x fp2gacl2 bph4
Organometallics, 2000Co-Authors: Keiji Ueno, Takahito Watanabe, Hiroshi OginoAbstract:Addition of 2,2‘-bipyridine (bpy) to an acetonitrile solution of Fp2GaCl (1: Fp = CpFe(CO)2; Cp = η-C5H5) afforded quantitatively a salt consisting of a diiron cation bridged by a Ga·bpy fragment ...
Werner Uhl - One of the best experts on this subject based on the ideXlab platform.
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A Carbon-Bridged DiGallium Compound as a Chelating Lewis Acid: Complexation of Thiophenolate and Benzoate Anions by H5C6−CH2−C(SiMe3)[Ga(CH2tBu)2]2
Organometallics, 2008Co-Authors: Werner Uhl, Michael Claesener, Alexander HeppAbstract:The diGallium compound H5C6−CH2C(SiMe3)(GaCl2)2 (6) is easily available by the 2-fold hydrogallation of phenyl(trimethylsilyl)ethyne with H−GaCl2. Its treatment with neopentyllithium gave the corresponding tetraneopentyl compound 7 by the replacement of all four chlorine Atoms. Compound 7 has two coordinatively unsaturated Gallium Atoms attached to one carbon Atom and, hence, is suitable to act as a chelating Lewis acid. Accordingly, tetrabutylammonium thiophenolate dissolved in 1,2-difluorobenzene reacted readily with 7 to afford the adduct 8, in which the sulfur Atom of the thiophenolato group is coordinated by both Gallium Atoms to form a four-membered CGa2S heterocycle. A similar compound (9) was formed upon treatment of 7 with the benzoate anion. A slightly different structural motif compared to 8 resulted because each oxygen Atom of the benzoate ligand is coordinated to one Gallium Atom to give a six-membered Ga2C2O2 heterocycle.
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1,4-Di(isopropyl)-1,4-diazabutadien als Abfangreagenz für monomere Bruchstücke des TetraGalliumclusters Ga4[C(SiMe3)3]4 – Bildung eines ungesättigten GaN2C2-Heterocyclus und eines Oxidationsprodukts mit Ga-O-O-Ga-Gruppe†
Zeitschrift für anorganische und allgemeine Chemie, 2005Co-Authors: Werner Uhl, Sandra Melle, Malte PröttAbstract:1,4-Di(isopropyl)-1,4-diazabutadiene as a Reagent for the Trapping of Monomeric Fragments of the TetraGalliumcluster Ga4[C(SiMe3)3]4 – Formation of an Unsaturated GaN2C2 Heterocycle and an Oxidation Product Containing a Ga-O-O-Ga Group The tetrahedral tetraGallium cluster Ga4[C(SiMe3)3]4 (1) dissociates upon dissolution to yield the monomeric fragments Ga-R [R = C(SiMe3)3]. These monomers could be trapped now by the treatment of their solutions with 1,4-di(isopropyl)-1,4-diazabutadiene. The product of the cycloaddition reaction (2) possesses a five-membered GaN2C2 heterocycle with a coordinatively unsaturated Gallium Atom and an endocyclic C=C double bond. 2 is rather sensitive towards oxidation by traces of air. The contact with oxygen yielded a diGallium peroxide [(C2N2iPr2)RGa-O-O-GaR(C2N2iPr2)] (3) which was isolated in a very low yield only and which has a Gallium Atom attached to each oxygen Atom of the inner peroxo group. Both chelating ligands of 3 possess an unpaired electron.
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Formation of a Gallium triphosphorus heterocycle by reaction of the alkylGallium(I) compound Ga4[C(SiMe3)3]4 with tri(tert-butyl)cyclotriphosphane
Journal of the Chemical Society Dalton Transactions, 2000Co-Authors: Werner Uhl, Maike BenterAbstract:Tri(tert-butyl)cyclotriphosphane reacted with Ga4[C(SiMe3)3]41 by the insertion of a monomeric GaR fragment into one of its P–P bonds. A four-membered, slightly folded GaP3 heterocycle was formed which has a co-ordinatively unsaturated Gallium Atom and all substituents in trans positions.
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OrganoGallium(II) compounds bearing chelating ligands, bridging versus terminal co-ordination of Gallium–Gallium single bonds
Chemical Society Reviews, 2000Co-Authors: Werner UhlAbstract:Tetrakis[bis(trimethylsilyl)methyl]digallane(4) 1 containing Gallium Atoms in an oxidation state of +II and a Ga–Ga single bond is a versatile starting compound for the synthesis of a broad variety of derivatives. One of the most exciting reactions is the substitution of alkyl groups without cleavage of the Ga–Ga bond, which succeeds by the treatment of 1 with chelating protonic acids such as carboxylic acids and acetylacetone derivatives. In all cases, two chelating ligands were introduced, which depending on their structural parameters either occupy terminal positions with each one co-ordinated to only one Gallium Atom or bridge the Ga–Ga bond. The reason for the different co-ordination behavior is discussed here.
Keiji Ueno - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and structure of a dmpe-substituted dinuclear complex bridged by a substituent-free Gallium Atom: Electronic effect of metal fragment on the iron–Gallium bonding
Journal of Organometallic Chemistry, 2006Co-Authors: Keiji Ueno, Masakazu Hirotsu, Naoki HatoriAbstract:Abstract A dinuclear complex bridged by a substituent-free Gallium Atom, Cp∗(dmpe)Fe–Ga–Fe(CO)4 (1b: Cp∗ = η-C5Me5, dmpe = Me2PCH2CH2PMe2), was synthesized by the reaction of Cp∗Fe(dmpe)GaCl2 with K2[Fe(CO)4]. Crystal structure analysis of complex 1b showed that the geometry around the Gallium Atom is essentially linear and the two Fe–Ga bonds are significantly shorter than those of usual single bonds, indicating the multiple bonding character of the Fe–Ga bonds. Comparison of the structure and IR data of 1b and those of Cp∗(dppe)Fe–Ga–Fe(CO)4 (1a: dppe = Ph2PCH2CH2PPh2) revealed that the Fe–Ga bond is sensitive to the electronic character of the metal fragment. The Fe–Ga bond is shortened upon introducing a more π-basic metal fragment.
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Synthesis and structure of the first dinuclear complex bridged by a substituent-free Gallium Atom
Organometallics, 2003Co-Authors: Keiji Ueno, Takahito Watanabe, Hiromi Tobita, Hiroshi OginoAbstract:The first dinuclear complex bridged by a substituent-free Gallium Atom, Cp*Fe(dppe)(μ-Ga)Fe-(CO) 4 (1; Cp* = η-C 5 Me 5 , dppe = Ph 2 PCH 2 CH 2 PPh 2 ), was synthesized by the reaction of Cp*Fe(dppe)GaCl 2 with K 2 [Fe(CO) 4 ]. A crystal structure analysis of complex 1 revealed that the geometry around the Gallium Atom is essentially linear and the Fe-Ga bonds are significantly shorter than that of usual single bonds. These structural features indicate that the Fe-Ga bonds bear significantly unsaturated character.
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synthesis of cationic diiron complexes bridged by a base stabilized Gallium Atom fp2 μ ga do2 x fp η c5h5 fe co 2 do2 2 2 bipyridine n n n n tetramethylethylenediamine 1 10 phenanthroline 4 dimethylamino pyridine 2 x fp2gacl2 bph4
Organometallics, 2000Co-Authors: Keiji Ueno, Takahito Watanabe, Hiroshi OginoAbstract:Addition of 2,2‘-bipyridine (bpy) to an acetonitrile solution of Fp2GaCl (1: Fp = CpFe(CO)2; Cp = η-C5H5) afforded quantitatively a salt consisting of a diiron cation bridged by a Ga·bpy fragment ...
Takahito Watanabe - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and structure of the first dinuclear complex bridged by a substituent-free Gallium Atom
Organometallics, 2003Co-Authors: Keiji Ueno, Takahito Watanabe, Hiromi Tobita, Hiroshi OginoAbstract:The first dinuclear complex bridged by a substituent-free Gallium Atom, Cp*Fe(dppe)(μ-Ga)Fe-(CO) 4 (1; Cp* = η-C 5 Me 5 , dppe = Ph 2 PCH 2 CH 2 PPh 2 ), was synthesized by the reaction of Cp*Fe(dppe)GaCl 2 with K 2 [Fe(CO) 4 ]. A crystal structure analysis of complex 1 revealed that the geometry around the Gallium Atom is essentially linear and the Fe-Ga bonds are significantly shorter than that of usual single bonds. These structural features indicate that the Fe-Ga bonds bear significantly unsaturated character.
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synthesis of cationic diiron complexes bridged by a base stabilized Gallium Atom fp2 μ ga do2 x fp η c5h5 fe co 2 do2 2 2 bipyridine n n n n tetramethylethylenediamine 1 10 phenanthroline 4 dimethylamino pyridine 2 x fp2gacl2 bph4
Organometallics, 2000Co-Authors: Keiji Ueno, Takahito Watanabe, Hiroshi OginoAbstract:Addition of 2,2‘-bipyridine (bpy) to an acetonitrile solution of Fp2GaCl (1: Fp = CpFe(CO)2; Cp = η-C5H5) afforded quantitatively a salt consisting of a diiron cation bridged by a Ga·bpy fragment ...
Yoshiki Chujo - One of the best experts on this subject based on the ideXlab platform.
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synthesis of aggregation induced emission active conjugated polymers composed of group 13 diiminate complexes with tunable energy levels via alteration of central element
Polymers, 2017Co-Authors: Shunichiro Ito, Kazuo Tanaka, Amane Hirose, Madoka Yamaguchi, Yoshiki ChujoAbstract:Conjugated polymers containing boron and Gallium diiminate complexes were prepared with various electron-donating comonomers via pre- and post-complexation methods, respectively. From a comparison of emission quantum yields between solution and film states, it was seen that all polymers containing group 13 elements possessed an aggregation-induced emission property. Additionally, the frontier orbital energies and the optical and electrochemical properties of the polymers can be tuned by altering a central element at the complex moieties as well as by changing a comonomer unit. In particular, it was demonstrated that the Gallium Atom can contribute to stabilizing the energy levels of the lowest unoccupied molecular orbitals, resulting in narrow band gaps of the conjugated polymers. This study presents the potential of Gallium not only for preparing solid-state emissive conjugated polymers but also for fabricating low-band gap materials by employing the conjugated ligand.
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Synthesis of air- and moisture-stable dibenzogallepins: control of planarity of seven-membered rings in solid states by coordination to Gallium Atoms.
Organic letters, 2015Co-Authors: Takuya Matsumoto, Hirofumi Takamine, Kazuo Tanaka, Yoshiki ChujoAbstract:Air- and moisture-stable dibenzo[b,f]gallepins with planar seven-membered rings have been designed and synthesized. From X-ray single-crystal analyses, the effects of the coordination numbers were evaluated at the Gallium Atom on the planarity of the seven-membered rings with a series of the synthesized complexes. Accordingly, it was shown that the seven-membered ring of dibenzogallepin involving a three-coordinated Gallium Atom presented the highest planarity compared to other dibenzogallepins with four- or five-coordinated Gallium Atoms. In addition, from theoretical calculations, it was proposed that the electronic states of the Gallium Atom in the complexes contributed to the energy levels of LUMOs+1.
