6917-81-3Relevant academic research and scientific papers
Redox-Active Ligand-Assisted Two-Electron Oxidative Addition to Gallium(II)
Fedushkin, Igor L.,Dodonov, Vladimir A.,Skatova, Alexandra A.,Sokolov, Vladimir G.,Piskunov, Alexander V.,Fukin, Georgii K.
, p. 1877 - 1889 (2018/01/27)
The reaction of digallane (dpp-bian)Ga?Ga(dpp-bian) (2) (dpp-bian=1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) with allyl chloride (AllCl) proceeded by a two-electron oxidative addition to afford paramagnetic complexes (dpp-bian)Ga(η1-All)Cl (3) and (dpp-bian)(Cl)Ga?Ga(Cl)(dpp-bian) (4). Treatment of complex 4 with pyridine induced an intramolecular redox process, which resulted in the diamagnetic complex (dpp-bian)Ga(Py)Cl (5). In reaction with allyl bromide, complex 2 gave metal- and ligand-centered addition products (dpp-bian)Ga(η1-All)Br (6) and (dpp-bian-All)(Br)Ga?Ga(Br)(dpp-bian-All) (7). The reaction of digallane 2 with Ph3SnNCO afforded (dpp-bian)Ga(SnPh3)2 (8) and (dpp-bian)(NCO)Ga?Ga(NCO)(dpp-bian) (9). Treatment of GaCl3 with (dpp-bian)Na in diethyl ether resulted in the formation of (dpp-bian)GaCl2 (10). Diorganylgallium derivatives (dpp-bian)GaR2 (R=Ph, 11; tBu, 14; Me, 15; Bn, 16) and (dpp-bian)Ga(η1-All)R (R=nBu, 12; Cp, 13) were synthesized from complexes 3, 10, Bn2GaCl, or tBu2GaCl by salt metathesis. The salt elimination reaction between (dpp-bian)GaI2 (17) and tBuLi was accompanied by reduction of both the metal and the dpp-bian ligand, which resulted in digallane 2 as the final product. Similarly, the reaction of complex 10 with MentMgCl (Ment=menthyl) proceeded with reduction of the dpp-bian ligand to give the diamagnetic complex [(dpp-bian)GaCl2][Mg2Cl3(THF)6] (18). Compounds 11, 12, 13, 15, and 16 were thermally robust, whereas compound 14 decomposed when heated at reflux in toluene to give complex (dpp-bian-tBu)GatBu2 (19). Both complexes 7 and 19 contain R-substituted dpp-bian ligand: in the former compound the allyl group was attached to the imino-carbon atom, whereas in complex 19, the tBu group was situated on the naphthalene ring. Crystal structures of complexes 3, 8, 9, 10, 13, 14, 18, and 19 were determined by single-crystal X-ray analysis. The presence of dpp-bian radical anions in 3, 6, 8, and 10–16 was determined by ESR spectroscopy.
PROCESS FOR PREPARING TRIALKYLGALLIUM COMPOUNDS
-
Paragraph 0114-0116, (2014/09/29)
The invention relates to a process for preparing trialkylgallium compounds of the general formula R3Ga. The process is based on the reaction of gallium trichloride (GaCh), optionally in a mixture with partially alkylated products, with an alkylaluminium compound of the type RaAlClb (where R═C1-C5-alkyl, a=1, 2 or 3, b=0, 1 or 2 and a+b=3) in the presence of at least two alkali metal halides (e.g. NaCl and KCl) as auxiliary base. Preference is given to using alkylaluminium sesquichloride (R3Al2Cl3) or trialkylaluminium (R3Al). The reaction mixture is heated to a temperature in the range from 120° C. to 250° C. and the trialkylgallium compound formed is separated off via a separator which is operated at a temperature which is more than 30° C. below the boiling point of the most volatile partially alkylated product. Complete alkylation is achieved here and partially alkylated products are recirculated to the reaction mixture. In a further step, the reaction mixture can be heated to a maximum of 350° C. and the remaining fully alkylated and partially alkylated products can be separated off. The process provides a high yield of trialkylgallium compound and displays high gallium utilization; the products are used, e.g., as precursors for MOCVD processes.
PROCESS FOR PREPARING TRIALKYLGALLIUM COMPOUNDS
-
Page/Page column 22, (2013/06/27)
The invention relates to a process for preparing trialkylgallium compounds of the general formula R3Ga. The process is based on the reaction of gallium trichloride (GaCh), optionally in a mixture with partially alkylated products, with an alkylaluminium compound of the type RaAICIb (where R = C1-C5-alkyl, a = 1, 2 or 3, b = 0, 1 or 2 and a + b = 3) in the presence of at least two alkali metal halides (e.g. NaCI and KCI) as auxiliary base. Preference is given to using alkylaluminium sesquichloride (R3AI2CI3) or trialkylaluminium (R3AI). The reaction mixture is heated to a temperature in the range from 120°C to 250°C and the trialkylgallium compound formed is separated off via a separator which is operated at a temperature which is more than 30°C below the boiling point of the most volatile partially alkylated product. Complete alkylation is achieved here and partially alkylated products are recirculated to the reaction mixture. In a further step, the reaction mixture can be heated to a maximum of 350°C and the remaining fully alkylated and partially alkylated products can be separated off. The process provides a high yield of trialkylgallium compound and displays high gallium utilization; the products are used, e.g., as precursors for MOCVD processes.
PROCESS FOR PREPARING TRIALKYL COMPOUNDS OF METALS OF GROUP IIIA
-
Page/Page column 15, (2013/06/27)
The invention relates to a process for preparing trialkylmetal compounds of the general formula R3M (where M = metal of group llIA of the Periodic Table of the Elements (PTE), preferably gallium or indium, and R = C1-C5-alkyl, preferably methyl or ethyl). The process is based on the reaction of metal trichloride (MeCl3) with alkylaluminium sesquichloride (R3AI2CI3) in the presence of at least one alkali metal halide as auxiliary base. The reaction mixture is heated to a temperature above 120°C and the trialkylmetal compound is separated off from the reaction mixture via a separator, with partially alkylated products being at the same time recirculated to the reaction mixture. In a further step, the reaction mixture is heated to a maximum of 350°C and the remaining alkylated and partially alkylated products are separated off. The products obtained in this way can optionally be recycled in the process. The process displays a high yield of trialkylmetal compound and also a high metal utilization; the products are used as precursors for MOCVD processes.
Aryl(dimethyl)gallium compounds and methyl(diphenyl)gallium: Synthesis, structure, and redistribution reactions
Jutzi, Peter,Izundu, Joseph,Neumann, Beate,Mix, Andreas,Stammler, Hans-Georg
, p. 4565 - 4571 (2009/02/07)
Treatment of diphenylmercury with an excess of trimethylgallium at higher temperatures resulted in the formation of dimethyl(phenyl)gallium (1). Similarly, reaction of 1-chloromercurio(4-methylbenzene) and 1-chloromercurio(4-tert-butylbenzene) with an excess of trimethylgallium gave dimethyl(4methylphenyl)gallium (2) and dimethyl(4-tert-butylphenyl)gallium (3), respectively. Treatment of diphenylmercury with an equivalent amount of trimethylgallium resulted in the formation of methyl(diphenyl)gallium (4). The X-ray crystallographic studies of compounds 1, 2, 3, and 4 revealed the presence of trigonal planar coordinate gallium atoms in monomeric molecules, which associate to polymeric strands by additional intermolecular gallium π-aryl contacts, thus leading to an overall trigonal bipyramidal coordination geometry at gallium. Compounds 1-4 are stable in the solid state and in solution. Substituent redistribution reactions take place at higher temperatures and at room temperature in the presence of THF. Compound 1 could also be prepared by the reaction of triphenylgallium with an excess of trimethylgallium at higher temperatures.
Synthesis and characterization of monomeric organogallium-nitrogen compounds, Et2GaNMe[C6H2(2,4,6-t-Bu)3], Me2GaNMe[C6H2(2,4,6-t-Bu)3], MeGa{NH[C6H2(2,4,6-t-Bu)3]}2, and Ga{NH[C6H2(2,4,6-t-Bu)3]}3
Beachley Jr.,Rosenblum, Daniel B.,MacRae, David J.
, p. 945 - 949 (2008/10/08)
Four gallium-nitrogen compounds, Et2GaNMe[C6H2(2,4,6-t-Bu)3], Me2GaNMe[C6H2(2,4,6-t-Bu)3], MeGa{NH[C6H2(2,4,6-t-Bu)3]}2, and Ga[N(H)C6H2(t-2,4,6-Bu)3]3 have been prepared by metathetical reactions. The monomeric derivatives Et2GaNMe[C6H2(2,4,6-t-Bu)3] and Me2-GaNMe[C6H2(2,4,6-t-Bu)3] are of interest because their 1H NMR spectra at room temperature had resonances indicative of two magnetically nonequivalent organic groups bonded to gallium, a spectral feature consistent with restricted rotation about the gallium-nitrogen bond. Variable-temperature 1H NMR spectral studies of a toluene solution of Me2GaNMe[C6H2(2,4,6-t-Bu)3] identified the barrier to rotation about the gallium-nitrogen bond as approximately 71 kJ/mol. This result suggests that steric effects might be responsible. The monomeric compound MeGa{NH[C6H2(2,4,6-t-Bu)3]}2 was prepared from MeGaCl2 and LiNH[C6H2(t-Bu)3] but was also the gallium-nitrogen product when Me2GaCl was reacted with the same lithium amide in diethyl ether. Experimental data demonstrated that Me2GaNH[C6H2(2,4,6-t-Bu)3] underwent a ligand redistribution reaction at room temperature to form an equilibrium mixture with MeGa{NH[C6H2(2,4,6-t-Bu)3]}2 and GaMe3. In contrast, the tertiary amide Ga{NH[C6H2(t-Bu)3]}3 does not readily undergo ligand redistribution reactions with GaMe3.
Ligand redistribution reactions of Me2Ga(C5H5) and MeGa(C5H5)2
Beachley, O. T.,Royster, T. L.,Arhar, J. R.
, p. 11 - 17 (2007/10/02)
The compounds Me2Ga(C5H5) and MeGa(C5H5)2 have been prepared by ligand redistribution reactions between appropiate stoichiometric quantities of Ga(C5H5) and GaMe3.Both compounds have been demonstrated by 1H NMR spectral studies to be unstable in solution and to form symmetrized products by ligand redistribution reactions.Thus, Me2Ga(C5H5) forms GaMe3 and MeGa(C5H5)2 as primary products whereas MeGa(C5H5)2 decomposes to Ga(C5H5)3 and Me2Ga(C5H5).The compound Me2Ga(C5H5) has also been shown to serve as a cyclopentadienyl transfer reagent as it reacts with FeCl2 to form Fe(C5H5)2 and Me2GaCl.
Synthesis and Properties of Bromo(methyl)- and Iodo(methyl)(organylthio)gallanes
Hoffmann, Gerhard G.
, p. 335 - 342 (2007/10/02)
The reaction between dibromo- or diiodo(methyl)gallane and the trimehylsilyl sulphides (CH3)3SiSR (R = CH3, C2H5, n-C3H7, i-C3H7, Ph, CH2Ph) have been investigated.Halo(methyl)(organylthio)gallanes are formed.These compounds and their chloro analogues can also be obtained by the reactions between the dihalo(methyl)gallanes and the corresponding leaddi(thiolates) in the molar ratios 2:1, or from the halo(dimethyl)gallanes and free thiols.Some physical and chemical properties of the new compounds are given, and the tentative mechanisms of these reactions are discussed.Syntheses of methylgalliumdiiodide and dimethylgalliumhalides via trimethylgallane and galliumtrihalides or methylgalliumdihalides are described. - Key words: Organogallium Derivatives, Trimethylsilyl Sulphides, Leaddi(thiolates), Synthesis, Properties
Dimethyl(alkylthio)- and Dimethyl(arylthio)gallanes - Synthesis and Properties
Hoffmann, Gerhard G.
, p. 1216 - 1218 (2007/10/02)
The nucleophilic substitution reactions between dimethylgalliumchloride (1) and the silyl sulfides (CH3)3SiSR (R = CH3, C2H5, n-C3H7, i-C3H7, Ph and CH2Ph) (2-7) in benzene result in the formation of the moisture-sensitive dimethyl(alkylthio)- and dimethyl(phenylthio)gallanes (CH3)3GaSR (R = CH3, C2H5, n-C3H7, i-C3H7, Ph and CH2Ph) (8-13).Compounds 8-11 are trimeric in benzene solutions, whereas compounds 12 and 13 appeared to be monomeric.The synthesis of dimethylgalliumchloride starting from trimethylgallane or methylgalliumdichloride and galliumtrichloride is reported as well. - Keywords: Dimethylgalliumchloride, Dimethyl(alkylthio)- and Dimethyl(arylthio) Compounds, Synthesis, Properties
