24597-12-4Relevant articles and documents
Dichlorogallane (HGACl2)2: Its molecular structure and synthetic potential
Nogai, Stefan,Schmidbaur, Hubert
, p. 4770 - 4774 (2002)
Dichlorogallane (HGaCl2)2 is readily prepared from gallium trichloride and triethylsilane in quantitative yield. Its crystal structure has been determined by single crystal X-ray diffraction. In the chlorine-bridged dimers of crystallographically imposed C2h symmetry, the terminal hydrogen atoms are in trans positions. In the reaction with 2 equiv of triethylphosphine, the mononuclear complex (Et3P)GaHCl2 is formed. Thermal decomposition of (HGaCl2)2 affords hydrogen gas and quantitative yields of GaCl2 as mixed-valent Ga[GaCl4]. Treatment of this product with triethylphosphine gives the symmetrical, Ga-Ga-bonded gallium(II) complex [GaCl2(PEt3)]2 with an ethane-type structure and with the phosphine ligands in a single-trans conformation. The corresponding [GaBr2(PEt3)]2 complex is prepared from Ga[GaBr4] and has an analogous structure. (Et3P)GaCl3 has been synthesized and structurally characterized as a reference compound.
A simple high-yield synthesis of gallium(I) tetrachlorogallate(III) and the reaction of digallium tetrachloride tetrahydrofuran solvate with 1,2-diols
Schmidt, Eva S.,Schier, Annette,Mitzel, Norbert W.,Schmidbaur, Hubert
, p. 337 - 341 (2001)
Gallium(I) tetrachlorogallate(III) Ga[GaCl4] was prepared in quantitative yield by thermal decomposition of dichlorogallane [HGaCl2]2, which is readily available from Et3SiH and [GaCl3]2. The reaction of catechol with solutions of this gallium(I) tetrachlorogallate(III) in tetrahydrofuran leads to the evolution of hydrogen gas and affords a dinuclear gallium(III) complex with penta-coordinate metal atoms chelated and bridged by mono-deprotonated catechol ligands. In the crystalline phase tetrahydrofuran molecules are hydrogen-bonded to the hydroxy groups: [Ga(1,2-OC6H4OH)Cl2(C4H 8O)]2. The reaction with pinacol also gives hydrogen and the analogous product [Ga(OCMe2CMe2OH)Cl2(C4H 8O)]2. The structures of the two compounds have been determined by X-ray diffraction. A mechanism of the new reaction has been proposed which involves oxidative addition of the diol to the solvate (THF)Cl2Ga-GaCl2(THF) present in the tetrahydrofuran solution to give a gallium hydride intermediate.
Gallium and gallium dichloride, new solid-state reductants in preparative transition metal chemistry. New, lower temperature syntheses and convenient isolation of hexatantalum tetradecachloride octahydrate
Hay, Daniel N. T.,Swenson, Dale C.,Messerle, Louis
, p. 4700 - 4707 (2002)
Reduction of TaCl5 with either Ga or Ga2Cl4, in the presence of NaCl, in a sealed borosilicate glass ampule at 500°C, followed by aqueous Soxhlet extraction and treatment with SnCl2 and hydrochloric acid, yielded Ta6(μ-Cl)12-Cl2 (OH2)4·4H2O in 92% (Ga) or 96% (Ga2Cl4) yield. Ga2Cl4, a probable intermediate in the Ga-based reduction, is a more convenient reductant than Ga because it is readily dispersed in the reaction mixture, and these mixtures do not require homogenizations in order to afford high yields. Ta6(μ-Cl)12Cl2 (OH2)4·4H2O was converted by ligand exchange to the first tetraalkylammonium derivative, [N(CH2Ph)Bu3]4[Ta6 [μ-Cl)12Cl6], of the reduced cluster core Ta6(μ-Cl)122+, in 88% yield. [N(CH2Ph)Bu3]4[Ta6 (μ-C)12Cl6] crystallizes from 1,2-dichloroethane/toluene mixtures in two crystalline morphologies, a nonsolvated cubic form and a solvated needle form. The solid-state molecular structures of both crystalline morphologies of [N(CH2Ph)Bu3]4[Ta6 (μ-Cl)12Cl6] consist of octahedral, 16 VEC hexatantalum cluster anions with an average Ta-Ta distance of 2.900[2] A, a Ta-Cl(bridge) distance of 2.463[2] A, a Ta-Cl(terminal) distance of 2.567[5] A, and a Ta-Cl-Ta angle of 72.1[1]° for the cubic form, and for the solvated needle morphology, an average Ta-Ta distance of 2.900[1] A, a Ta-Cl(bridge) distance of 2.461[1]A, a Ta-Cl(terminal) distance of 2.567[3] A, and a Ta-Cl-Ta angle of 72.19[7]°.
The Structure of Solutions of Gallium(I) Chloride in Benzene
Ulvenlund, Stefan,Wheatley, Andrew,Bengtsson, Lars A.
, p. 245 - 254 (1995)
The structure of benzene solutions of Ga and Ga has been investigated by 13C and 71Ga NMR, Raman spectroscopy and liquid X-ray scattering (LXS).Assignments of the vibrational spectra are based on a reinvestigation of the liquid Ga-GaCl3 system.The results for the Ga-C6H6 system are in agreement with the view that an ion pair between Ga(1+) and GaCl4(1-), which lowers the symmetry of the GaCl4(1-) ion from Td to C2v or lower, is formed.Spectroscopic effects indicating a complex formation between Ga(1+) and benzene are weak.The salt Ga was found to be extremely soluble in benzene ( >50percent w/w).The results imply that in such solutions the Ga-Clb-Ga bridge in the Ga2Cl7(1-) ion is bent and the ion pairing between Ga(1+) and Ga2Cl7(1-) takes place via the bridging chloride ion of the latter ion.Results from LXS show that the Ga(III)-Clb distance is remarkably long, 2.85 Angstroem (24percent longer than in solid K).For this system, 71Ga and 13C NMR as well as Raman spectroscopic results clearly indicate complex formation between Ga(I) and benzene.
Decomposition of monochlorogallane, [H2GaCl]n, and adducts with amine and phosphine bases: Formation of cationic gallane derivatives
Tang, Christina Y.,Downs, Anthony J.,Greene, Tim M.,Marchant, Sarah,Parsons, Simon
, p. 7143 - 7150 (2008/10/09)
Thermal decomposition of monochlorogallane, [H2GaCl] n, at ambient temperatures results in the formation of subvalent gallium species. To Ga[HGaCl3], previously reported, has now been added a second mixed-valence solid, Ga4-[HGaCl3] 2[Ga2Cl6] (1), the crystal structure of which at 150 K shows a number of unusual features. Adducts of monochlorogallane, most readily prepared from the hydrochloride of the base and LiGaH4 in appropriate proportions, include not only the 1:1 molecular complex Me 3P·GaH2Cl (2), but also 2:1 amine complexes which prove to be cationic gallane derivatives, [H2Ga(NH2R) 2]+Cl-, where R = tBu (3a) or sBu (3b). All three of these complexes have been characterized crystallographically at 150 K.
Some chemical properties of monochlorogallane: Decomposition to gallium(I) trichlorogallate(III), Ga+[GaCl3H]-, and other reactions
Johnsen,Downs,Goode,Greene,Himmel,Mueller,Parsons,Pulham
, p. 4755 - 4761 (2008/10/08)
Thermal decomposition of monochlorogallane, [H2GaCl]n, at ambient temperatures releases H2 and results in the formation of gallium(I) species, including the new compound Ga[GaHCl3], which has been characterized crystallographically at 100 K (monoclinic P21/n, a = 5.730(1), b = 6.787(1), c = 14.508(1) A, β = 97.902(5)°) and by its Raman spectrum. The gallane suffers symmetrical cleavage of the Ga(μ-Cl)2Ga bridge in its reaction with NMe3 but unsymmetrical cleavage, giving [H2Ga(NH3)2]+Cl-, in its reaction with NH3. Ethene inserts into the Ga-H bonds to form first [Et(H)GaCl]2 and then [Et2GaCl]2.
