Synthesis, Structure, and Properties of Gallium Compounds with the Heterodifunctional [2-(N,N-Dimethylamino)ethyl]cyclopentadienyl Ligand¹

Abstract

Several new gallium compounds containing the [2-(N,N-dimethylamino)ethyl]cyclopentadienyl ligand (Cp N ) are described. Reaction of the respective element halide with Cp N K 1 leads to the compounds 2-6 of the type [2-(Me 2 NCH 2 CH 2 )C 5 H 4 ]GaX 2 [2: X ) Cl; 3: X ) Br; 4: X ) I; 5: X ) CH 3 ; 6: X ) H]. Each compund was characterized by 1 H and 13 C NMR spectroscopy, mass spectrometry, and elemental analysis; the molecular structures of 2-5 were determined by X-ray crystallography. In the solid state and presumably also in solution all compounds feature a monomeric structure with an intramolecularly coordinated dimethylamino group. The resulting coordinative and electronic saturation of the metal center leads to a drastically decreased reactivity against moisture and air. The observed dynamic behavior in solution is based on fast haptotropic shifts in a "windscreen-wiper" type process. Sufficient volatility and well-behaved fragmentation makes 6 a suitable precursor for the deposition of gallium in the MOCVD process.

A donor–acceptor adduct: sterically encumbered terphenyl dichloro[2,6-bis(2,4,6-triisopropylphenyl)phenyl]dichloro(pyridine)gallium benzene hemisolvate

“…The average GaÐC and GaÐCl bonds [1.985 (7) and 2.195 (2) A Ê , respectively; Table 1] are slightly longer than analogous bonds in the base-free chloride 2,6-Trip 2 -C 6 H 3 -GaCl 2 [Twamley & Power, 1999;1.930 (8) A Ê , and 2.124 (3) and 2.113 (4) A Ê , respectively] obviously due to the electronic effect of the pyridine donation. The GaÐN distances in (1) [2.028 (6)±2.040 (7) A Ê ] are in good agreement with the corresponding bonds in previously reported gallium chloride complexes that have coordination GaÐN bonds in chelate cycles [GaÐN 2.034 (8)±2.071 (2) A Ê ; Al-Juaid et al, 1999; Jutzi et al, 1996;Isom et al, 1995]. The torsion angles about the four rotatable bonds in each of the independent molecules [GaÐN, GaÐC ipso , two ortho-CÐC (ipso pendant phenyl group); see Table 1] show that all four molecules have essentially similar geometry.…”

Synthese, Röntgenstrukturanalyse und Multikern-NMR-spektroskopische Untersuchung einiger intramolekular stickstoffstabilisierter Bor-, Aluminium- und Galliumorganyle

“…2,1886(6) A Ê ). Entsprechend der in den Dichloridverbindungen im Vergleich zu analogen Alkylderivaten stark erho È hten Lewis-Acidita È t des Metallzentrums [25] zeigen die bereits bekannten Galliumalkyle Me 2 GaC 6 H 4 -2-CH 2 NMe 2 [6 b], (CH 2 ) 5 Ga(CH 2 ) 3 NMe 2 und (CH 2 ) 5 GaCH 2 CHMeCH 2 NMe 2 [6 e] vergleichsweise la Èngere Ga±N Bindungen im Bereich von 2,133(2) bis 2,154(2) A Ê .…”

Gallium Hydride Complexes Stabilised by Multidentate Alkoxide Ligands: Precursors to Thin Films of Ga2O3 at Low Temperatures

“…The reason for this is not clear and may be due to crystal packing effects, but both Ga À N bond lengths are in the range of known dative Ga À N bonds which are part of a chelating ligand (2.028(5)-2.000 (3) ). [12,24] The Li À O distance is also typical of Li À O bonds found as part of a chelating ligand (1.853(6)-1.885 (13) ). [25,26] The bond angles around the gallium centre are an indication of how close the geometry of 6·LiCl is to ideal trigonal bipyramidal.…”