59487-11-5Relevant articles and documents
Rational Development of Cobalt β-Ketoiminate Complexes: Alternative Precursors for Vapor-Phase Deposition of Spinel Cobalt Oxide Photoelectrodes
Junge Puring, Kai,Zywitzki, Dennis,Taffa, Dereje H.,Rogalla, Detlef,Winter, Manuela,Wark, Michael,Devi, Anjana
, p. 5133 - 5144 (2018)
A series of six cobalt ketoiminates, of which one was previously reported but not explored as a chemical vapor deposition (CVD) precursor, namely, bis(4-(isopropylamino)pent-3-en-2-onato)cobalt(II) ([Co(ipki)2], 1), bis(4-(2-methoxyethylamino)pent-3-en-2-onato)cobalt(II) ([Co(meki)2], 2), bis(4-(2-ethoxyethylamino)pent-3-en-2-onato)cobalt(II) ([Co(eeki)2], 3), bis(4-(3-methoxy-propylamino)pent-3-en-2-onato)cobalt(II) ([Co(mpki)2], 4), bis(4-(3-ethoxypropylamino)pent-3-en-2-onato)cobalt(II) ([Co(epki)2], 5), and bis(4-(3-isopropoxypropylamino)pent-3-en-2-onato)cobalt(II) ([Co(ippki)2], 6) were synthesized and thoroughly characterized. Single-crystal X-ray diffraction (XRD) studies on compounds 1-3 revealed a monomeric structure with distorted tetrahedral coordination geometry. Owing to the promising thermal properties, metalorganic CVD of CoOx was performed using compound 1 as a representative example. The thin films deposited on Si(100) consisted of the spinel-phase Co3O4 evidenced by XRD, Rutherford backscattering spectrometry/nuclear reaction analysis, and X-ray photoelectron spectroscopy. Photoelectrochemical water-splitting capabilities of spinel CoOx films grown on fluorine-doped tin oxide (FTO) and TiO2-coated FTO revealed that the films show p-type behavior with conduction band edge being estimated to -0.9 V versus reversible hydrogen electrode. With a thin TiO2 underlayer, the CoOx films exhibit photocurrents related to proton reduction under visible light.
Metal β-diketoiminate precursor use in aerosol assisted chemical vapour deposition of gallium- and aluminium-doped zinc oxide
Knapp, Caroline E.,Dyer, Caragh,Chadwick, Nicholas P.,Hazael, Rachael,Carmalt, Claire J.
, p. 35 - 41 (2018)
Aerosol assisted chemical vapour deposition (AACVD) has been used to deposit thin films of ZnO from the single-source precursor [Zn(OC(Me)CHC(Me)N(iPr))2] (1) affording highly transparent (>80%) and conductive films (sheet resistance ~70 KΩ/sq). Extension of this AACVD method whereby related precursors of the type, [R2M(OC(Me)CHC(Me)N(iPr))] (R = Et, M = Al (2); R = Me, M = Ga (3)), isolated as oils, were added to the precursor solution allowed for the deposition of aluminium- and gallium-doped ZnO (AZO and GZO) films, respectively. Complexes 1–3 were characterised by elemental analysis, NMR and mass spectrometry. Films were deposited in under 30 min at 400 °C, from CH2Cl2/toluene solutions with a N2 carrier gas. Herein we report the bulk resistivity, ρ, of AZO (0.252 Ω cm) and GZO (0.756 Ω cm) films deposited from this novel approach. All the films transparency exceeded 80% in the visible, X-ray diffraction (XRD) showed all films to crystallise in the wurtzite phase whilst X-ray photoemission spectroscopy (XPS) confirmed the presence of the Al and Ga dopants in the films, and highlighted the low C-contamination (a mechanism analogous to the Kirkendall effect confirmed that heating of GZO films at 1000 °C produced the spinel structure GaZn2O4.
Dinuclear cobalt complexes supported by biphenol and binaphthol-derived bis(salicylaldimine) ligands: synthesis, characterization and catalytic application in β-enaminone synthesis from 1,3-dicarbonyl compounds and aliphatic amines
Filkale, Adelew Estifanos,Pathak, Chandni
supporting information, p. 15109 - 15121 (2020/09/23)
Two new tetradentate ligands, namely, 3,3′-bis[((2,4,6-trimethyl-phenyl)imino)methyl]-[1,1′]-biphenyl-2,2′-diol,H2L1(1), and 3,3′-bis[((2,4,6-trimethylphenyl)imino)methyl]-[1,1′]-binaphthalenyl-2,2′-diol,H2L2(3), based on 2,2′-biphenol and 2,2′-binaphthol frameworks have been synthesized and characterized. Correspondingly, dinuclear cobalt complexes {Co[3,3′-bis-((R)-iminomethyl)-(1,1′)-biphenyl-2,2′-dioxo]}2(2) and {Co[3,3′-bis-((R)-iminomethyl)-(1,1′)-binaphthalenyl-2,2′-dioxo]}2(4) (where R = 2,4,6-Me3C6H2) were synthesizedviareactions of the respective ligands with tetrahydrate cobalt acetate. The complexes were then characterized by elemental analysis, mass spectrometry, IR, UV-vis, magnetic susceptibility and single-crystal X-ray diffraction analysis. The single-crystal X-ray crystallographic study indicates a distorted tetrahedral geometry for each of the metal ions in2and4. The magnetic susceptibility measurements at varying temperatures (5-300 K) showed that the complexes exhibit weak antiferromagnetic (AF) interactions. Both metal complexes2and4successfully catalysed the synthesis of β-enaminones from 1,3-dicarbonyl compounds and aliphatic amines under ambient conditions.
Redox Property of Enamines
Li, Yao,Wang, Dehong,Zhang, Long,Luo, Sanzhong
, p. 12071 - 12090 (2019/10/11)
Enamines are electron-rich compounds bearing intriguing redox properties. Herein, a series of secondary enamines condensed from primary amine and β-ketocarbonyls were synthesized and their electrochemical oxidation properties were systematically studied by cyclic voltammetry. Furthermore, theoretical calculation of oxidation potentials of enamines, particularly those catalytic intermediates, was also conducted to further broaden the scope investigated. Possible structural factors on oxidation and the nature of the resulted radical cation intermediates were revealed and discussed. Correlation of redox potentials with molecular properties such as highest occupied molecular orbital energies and natural population analysis charge were explored, and there appears no simple linear correlation. On the other hand, a good correlation with Mayr's nucleophilicity parameter N was noted among a range of catalytically relevant enamines. Spin population analysis disclosed that enamine radical cations mainly exhibit the carbon-center free radical feature. Taking experimental and computation data together, a comprehensive picture about the redox property of enamines is presented, which would provide guidance in the development of oxidative enamine catalysis and transformations.