Diorgano-Gallium and -Indium Complexes Derived from Benzoazole Ligands: Synthesis, Characterization, Photoluminescence, and Computational Studies

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• 作者：Manoj K. Pal ; Nisha Kushwah ; Debashree Manna ; Amey Wadawale ; V. Sudarsan ; Tapan K. Ghanty ; Vimal K. Jain
• 刊名：Organometallics
• 出版年：2013
• 出版时间：January 14, 2013
• 年：2013
• 卷：32
• 期：1
• 页码：104-111
• 全文大小：457K
• 年卷期：v.32,no.1(January 14, 2013)
• ISSN：1520-6041

文摘

The reactions of triorgano-gallium and -indium etherate with benzoazole ligands 2-(2鈥?hydroxyphenyl)benzoxazole (Hhbo) (1a), 2-(2鈥?hydroxyphenyl)benzothiazole (Hhbt) (1b), and 2-(2鈥?hydroxyphenyl)benzimidazole (Hhbi) (1c) in benzene yielded complexes of the type [R₂ML]_n with n = 1 for gallium and 2 for indium (where R = Me, Et; M = Ga, In; L = hbo, hbt, and hbi) in nearly quantitative yields. These complexes have been characterized by elemental analysis, IR, UV鈥搗is, and NMR (¹H and ¹³C{¹H}) spectroscopy. Photoluminescence studies of these complexes showed that the quantum yield is always higher than that of the corresponding ligands due to reduced intermolecular interactions in complexes as compared to free ligands. The molecular structures of [Me₂Ga(hbo)] (2a) and [Me₂In(渭-hbt)]₂ (3b) were established by X-ray crystallography. The analyses revealed that the gallium complex exists as a four-coordinated monomer, whereas the indium complex forms a dimer comprising five-coordinated indium atoms. Density functional calculations have been carried out for computing the structural and energetic parameters of the complexes, which indicate that the formation of the monomer is favorable with the Ga³⁺ ion, whereas the dimeric structure is preferred with the In³⁺ ion.