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首页> 外文期刊>Polyhedron: The International Journal for Inorganic and Organometallic Chemistry >Physicochemical approach to the studies of metal alkoxides [Review]
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Physicochemical approach to the studies of metal alkoxides [Review]

机译：金属醇盐研究的物理化学方法[综述]

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The review provides a description of main events in the development of chemistry of metal alkoxides in Russian and summarizes the results obtained by the authors. The studies of solubility and vapor pressure in the M(OR)(n)-ROH (R = Li, Mg, Ca, Sr, Ba, Tl) systems permitted the determination of the composition of the solvates formed and the optimization of the isolation conditions for distinct derivatives. The electrochemical synthetic approach to the alkoxide and 2-methoxyethoxide derivatives of III-VIII Group elements has been elaborated. Improvement of the MCln with NaOR metathesis conditions led to practically quantitative yields of alkoxides. The examples of the structures of polynuclear oxoalkoxides, earlier erroneously considered to be orthoderivatives, i.e. 'M(OR)(n)', are given. It has been stated that among the alkoxoderivatives of Zr and I-If these are only M(OC2H4OMe)(4) and M(OR)(4) . ROH (R = Pr', Bu') that exist as individual compounds, while the samples of those with different R contain oxocomplexes of M3O(OR)(10) and M4O(OR)(14) composition. The questions connected with the origin of oxogroups in the molecules of alkoxides and their influence on the properties of the samples are discussed. The irreproducibility of the physicochemical constants for the samples (physical state, melting points, solubility in alcohols, intensity of coloration) is caused by different 'chemical' (synthetic procedures, isolation conditions) and thermal prehistory and storage times; it originates from the difference in their molecular composition (different fractions of different types of oligomeric and polymeric [M(OR)(n)](m) and MxOy(OR)(z) aggregates). Formation of bimetallic alkoxides is studied using the plotting of 20 degrees C solubility isotherms in M(OR)(n)- M'(OR)(m)-Solvent systems. Different kinds of systems are considered and the composition and structure of bimetallic complexes and oxocomplexes, originating from their decomposition, are described. Decomposition of alkoxomolybdates and -tungstates in solutions may result in crystallization of complex oxides as the final products. The example of MTiO3 (M = Mg, Ba) oxide preparation is discussed as most illustratively demonstrating the need in studies of metal alkoxides interaction in solution for the optimization of synthesis of oxides by the sol-gel technique. (C) 1998 Elsevier Science Ltd. All rights reserved. [References: 116]
机译：这篇综述描述了俄语中金属醇盐化学发展中的主要事件，并总结了作者获得的结果。对M（OR）（n）-ROH（R ​​= Li，Mg，Ca，Sr，Ba，Tl）系统中的溶解度和蒸气压的研究可以确定所形成的溶剂化物的组成并优化分离不同衍生工具的条件。已经阐明了III-VIII族元素的醇盐和2-甲氧基乙氧化物衍生物的电化学合成方法。使用NaOR复分解条件改善MCln导致实际上定量的醇盐收率。给出了先前被错误地认为是正衍生物的多核氧代烷氧化物的结构实例，即“ M（OR）（n）”。有人指出，在Zr和I-的烷氧基衍生物中，如果只有M（OC2H4OMe）（4）和M（OR）（4）。 ROH（R ​​= Pr'，Bu'）作为单独的化合物存在，而具有不同R的那些样品包含M3O（OR）（10）和M4O（OR）（14）组成的氧配合物。讨论了与醇盐分子中氧代基团的起源及其对样品性质的影响有关的问题。样品的物理化学常数（物理状态，熔点，在醇中的溶解度，着色强度）的不可再现性是由不同的“化学”（合成程序，分离条件）以及热史前和存储时间引起的;它源自分子组成的差异（不同类型的低聚和聚合[M（OR）（n）]（m）和MxOy（OR）（z）聚集体的不同馏分）。使用M（OR）（n）-M'（OR）（m）-溶剂系统中20摄氏度的溶解度等温线作图，研究了双金属醇盐的形成。考虑了不同种类的系统，并描述了源自其分解的双金属配合物和氧代​​配合物的组成和结构。溶液中烷氧钼酸盐和钨酸盐的分解可能导致作为最终产物的复杂氧化物的结晶。讨论了MTiO3（M = Mg，Ba）氧化物制备实例，最能说明性地说明了研究溶液中金属醇盐相互作用以优化通过溶胶-凝胶技术合成氧化物的必要性。 （C）1998 Elsevier ScienceLtd。保留所有权利。 [参考：116]

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