【摘要】 本文利用原位红外光谱方法研究了三钌乙烯酮化合物在无机载体SiO₂、SiO₂-Al₂O₃和MgO表面上的负载,发现[Ru₃（CO）₉（CCO）]^2-分别同SiO₂和SiO₂-Al₂O₃表面上的羟基反应,选择性地定量形成[HRu₃（CO）₉（CCO）]^-/SiO₂和H₂Ru₃（CO）₉（CCO）/SiO₂-Ai₂O₃,而在MgO表面上,[Ru₃（CO）₉（CCO）]^2-保持其结构。对¹³CO同位素交换,H₂Ru₃（CO）₉（CCO）/SiO₂-Al₂O₃显示了很高活性,而[Ru₃（CO）₉（CCO）]^2-/MgO则完全不反应。在甲基化反应中,[Ru₃（CO）₉（CCO）]^2-/MgO对CH₃I显示了很高活性,但对CH₃Li却不反应,对H₂Ru₃（CO）₉（CCO）/SiO₂-Al₂O₃,它与CH₃I不显示活性,但却和CH₃Li较易反应;[HRu₃（CO）₉（CCO）]^-/SiO₂的甲基化的活性顺序处于上述MgO和SiO₂-Al₂O₃担体上的簇合物之间。通过乙烯甲酰化反应可以看到,在(Ru₃（CO）₉（CCO）]^2-/MgO上,对于含氧化合物的形成显示了高活性,而对于H₂Ru₃（CO）₉（CCO）/SiO₂-Al₂O₃则有利于形成烃类化合物。更多还原

【Abstract】 The product distribution in a series of catalytic reactions by sup-ported metal catalysts is markedly influenced by the nature of the oxide supports. Metal cluster grafted on oxide supports as a model catalyst. offers an opportunity to understand the elementary steps of heterogeneous catalytic reactions and the metal-support interaction in terms ot surface organometallic chemistry. In this paper, triruthe- rium ketenylidene cluster as a possible intermediate in CO hydrogena-tion over supported metal catalysts is impregnated on SiO2,SiO2-Al2O3 and MgO. The structure and catalytic behavior of the resulted catalysts are investigated by in situ IR spectroscopy and other techniques.When [PPN]2[Ru3 (CO ) 9 (CCO ) ] is supported on the surface of SiO2, SiO2-Al2O3 and MgO at room temperature from the CH2C12 solution in an in situ IR cell, the resulted samples give rise to quite different carbonyl bands in the region from 1750-2150 cm-1. Through comparison of the characteristic bands of various triruthenium ketenylidene clusters in CH2C12 and on oxide-surface, it is suggested that [Ru3 ( CO ) 9 ( CCO )]2- reacts with Si-OH of SiO2 and Si ( OH ) Al of SiO2-Al2O3, resulting in the selective formation of [HRu3(CO)9 (CCO )]-/SiO2, H2Ru3 (CO )9 (CCO )/SiO2-Al2O3 and [Ru3(CO)9 ( CCO )]2-/MgO, respectively. In the meantime, the sample of [HRu3 ( CO ) 9 ( CCO )]-/SiO2 shows a new band at 694 cm-1, which is likely associated with the out-of-plane bending of Ru-H-Ru.In 13CO exchange reaction, it proceeds with a higher rate on H2Ru3 (CO )9(CCO )/SiO2-Al2O3 than on [HRu3 ( CO ) 9( CCO)]-/SiO2. The admission of 13CO at 300-373 K on H2Ru3 ( CO )9( CCO ) /SiO2-Al2O3 leads to the facile exchange of the carbonyl bands. In contract ,[HRu3 (CO )9 (CCO )]-/SiO2 and [Ru3 ( CO ) 9( CCO )]3-/MgO show very low activities even at high temperature. The order of activity is as follows; H2Ru3 ( CO ) 9 ( CCO ) /SiO2-Al2O3>> [HRu3 ( CO )9 ( CCO )]-/ SiO2>[Ru3 (CO )9 (CCO ) ]2-/MgO, which is likely to depend on the formal charges of the oxide-grafted ketenylidene clusters.Tn alkylation reaction, the reaction of [Ru3 ( CO)9 ( CCO )]2-/MgO with CH3I at room temperature proceeds very fast, resulting in [Ru3 (CO ) 9CC ( O ) CH3]3-/MgO, showing a 1635cm-1 band that is ascribed to the carbonyl stretching frequency of the acyl moiety. In contrast, H2Ru3(CO)9 (CCO)/SiO2-Al2O3 is completely inactive with CH3I up to 570 K, but it is very easy to react with CH3Li at room temperature.In hydroformylation of ethylene on oxide-supported trirutheniumketenylidene cluster, a higher rate for oxygenates is observed on MgO-supported dianion cluster derived catalyst than on SiO2 or SiO2-Al2O3 -supported ones. The orders of activity and selectivity for ethane andoxygenates on various oxides used are as follows:Activity for oxygenates: MgO>SiO2>SiO2-A12O3.Selectivity for alcohol: MgO>>SiO2, SiO2-Al2O3.Activity for ethane: SiO 2 - A12O 3>SiO 2>MgO.更多还原