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• 作者：Zdenek Moravec ; Radek Sluka ; Marek Necas ; Vojtech Jancik ; Jiri Pinkas
• 刊名：Inorganic Chemistry
• 出版年：2009
• 出版时间：September 7, 2009
• 年：2009
• 卷：48
• 期：17
• 页码：8106-8114
• 全文大小：924K
• 年卷期：v.48,no.17(September 7, 2009)
• ISSN：1520-510X

文摘

A diverse series of aluminum chloride alkoxides, [Cl_xAl(μ-OR)_y]_n (R = ⁿBu, ^cHex, Ph, 2,4-^tBu₂C₆H₃), was synthesized using the reactions of dichlorethylalane (EtAlCl₂) with cyclohexanol (^cHexOH), n-butanol (ⁿBuOH), and phenols (PhOH and 2,4-^tBu₂C₆H₃OH). Eight molecular products were isolated and structurally characterized. The dimeric [Cl₂Al(μ-O^cHex)₂AlCl₂] (1) was the smallest oligomer isolated among the cyclohexanolate derivatives. The adduct of 1 with cyclohexanol is a dinuclear molecule [Cl₂(HO^cHex)Al(μ-O^cHex)₂AlCl₂] (2) which represents a possible intermediate in the conversion reaction leading to the formation of a trinuclear bicyclic [ClAl{(μ-O^cHex)₂AlCl₂}₂] (3). Two polymorphic forms of 3 were isolated. Further coordination of cyclohexanol to the Lewis acidic five-coordinate aluminum atom in 3 provided [Cl(HO^cHex)Al{(μ-O^cHex)₂AlCl₂}₂] (4) with octahedrally coordinated central aluminum. Compound 4 could be regarded as a precursor to the well-known Mitsubishi (tridiamond) tetranuclear species. The reactions of EtAlCl₂ with less sterically demanding ⁿBuOH yielded a cyclic trimer, [Cl₂Al(μ-OⁿBu)]₃ (5), and a unique trinuclear ionic species, [Cl₂Al{(μ-OH)(μ-OⁿBu)AlCl(HOⁿBu)₃}₂]Cl (6) with a linear Al(μ-O)₂Al(μ-O)₂Al core. In the reactions with phenols, the aromatic groups preferentially stabilized dimeric structures of [Cl₂Al(μ-OR)₂AlCl₂] (R = Ph, 7; 2,4-^tBu₂C₆H₃, 8). Since these compounds could be considered as intermediates in the nonhydrolytic condensation reactions of metal halides with metal alkoxides, a mixture of EtAlCl₂ with ^cHexOH was used as a precursor for the nonaqueous synthesis of alumina by alkylhalide elimination.