Gallium and Indium β-diketonate complexes: AACVD of [In(thd) ₃] and the attempted synthesis of gallium and indium bis(β-diketonates)

TY - JOUR

T1 - Gallium and Indium β-diketonate complexes

T2 - AACVD of [In(thd) 3] and the attempted synthesis of gallium and indium bis(β-diketonates)

AU - Pugh, David

AU - Bloor, Leanne G.

AU - Sathasivam, Sanjayan

AU - Parkin, Ivan P.

AU - Carmalt, Claire J.

PY - 2011/4

Y1 - 2011/4

N2 - Aerosol-assisted chemical vapour deposition (AACVD) of a suspension of [In(thd)3] (thd = 2,2,6,6-tetramethylheptane-3,5-dionate) in CH 2Cl2 at 450 °C afforded thin crystalline films of indium oxide. The films were analyzed by scanning electron microscopy (SEM), glancing angle X-ray diffraction (XRD) and energy dispersive analysis of X-rays (EDX). Efforts to grow thicker films were hampered by the poor solubility of [In(thd)3], so the synthesis of heteroleptic compounds of the type [M(bdk)2X] (M = Ga, In; bdk = β-diketonate; X = chloride, hydride, methyl) was attempted such that the solubility could be improved by tuning the ligands surrounding the metal centre. Reaction of stoichiometric amounts of β-diketones [Hthd and 2,4-pentanedione (acetylacetone, Hacac)] with Lewis base-stabilized adducts of GaH3 resulted only in the isolation of the homoleptic gallium tris(β-diketonate) compounds [Ga(bdk)3], instead of the expected heteroleptic gallium bis(β-diketonate) hydride, [GaH(bdk)2]. An unexpected reduction of Hthd to 2,2,6,6-tetramethylheptane-3,5-diol was also observed. Other attempted syntheses of gallium bis(β-diketonate) compounds also resulted in the isolation of homoleptic [Ga(bdk)3] complexes and similar results were obtained for indium. The compounds were characterised by 1H NMR spectroscopy, mass spectrometry and elemental analysis and the structures of [In(thd)3] and 2,2,6,6-tetramethylheptane-3,5-diol were determined by X-ray crystallography.

AB - Aerosol-assisted chemical vapour deposition (AACVD) of a suspension of [In(thd)3] (thd = 2,2,6,6-tetramethylheptane-3,5-dionate) in CH 2Cl2 at 450 °C afforded thin crystalline films of indium oxide. The films were analyzed by scanning electron microscopy (SEM), glancing angle X-ray diffraction (XRD) and energy dispersive analysis of X-rays (EDX). Efforts to grow thicker films were hampered by the poor solubility of [In(thd)3], so the synthesis of heteroleptic compounds of the type [M(bdk)2X] (M = Ga, In; bdk = β-diketonate; X = chloride, hydride, methyl) was attempted such that the solubility could be improved by tuning the ligands surrounding the metal centre. Reaction of stoichiometric amounts of β-diketones [Hthd and 2,4-pentanedione (acetylacetone, Hacac)] with Lewis base-stabilized adducts of GaH3 resulted only in the isolation of the homoleptic gallium tris(β-diketonate) compounds [Ga(bdk)3], instead of the expected heteroleptic gallium bis(β-diketonate) hydride, [GaH(bdk)2]. An unexpected reduction of Hthd to 2,2,6,6-tetramethylheptane-3,5-diol was also observed. Other attempted syntheses of gallium bis(β-diketonate) compounds also resulted in the isolation of homoleptic [Ga(bdk)3] complexes and similar results were obtained for indium. The compounds were characterised by 1H NMR spectroscopy, mass spectrometry and elemental analysis and the structures of [In(thd)3] and 2,2,6,6-tetramethylheptane-3,5-diol were determined by X-ray crystallography.

KW - Chemical vapor deposition

KW - Gallium

KW - Indium

KW - Thin films

UR - http://www.scopus.com/inward/record.url?scp=79953904655&partnerID=8YFLogxK

U2 - 10.1002/ejic.201001235

DO - 10.1002/ejic.201001235

M3 - Article

AN - SCOPUS:79953904655

SN - 1434-1948

SP - 1953

EP - 1960

JO - EUROPEAN JOURNAL OF INORGANIC CHEMISTRY

JF - EUROPEAN JOURNAL OF INORGANIC CHEMISTRY

IS - 12

ER -