FeO催化乙炔三聚环化气相反应机理的理论研究  

A DFT study of the acetylene cyclotrimerization catalyzed by FeO in the gas phase

作　　者：陈曙[1] 鞠廷勇[1] 杨华清[1] 

机构地区：[1]四川大学化学工程学院,四川成都610065

出　　处：《化学研究与应用》2014年第6期928-932,共5页Chemical Research and Application

基　　金：国家自然科学基金(No.21343001;91016002和20976109);四川省应用基础研究(No.2011JY0024)

摘　　要：在B3LYP/aug-cc-pvtz//6-311++G(2d,2p)水平下研究了气相FeO分子催化乙炔三聚环化合成苯的反应机理。研究结果表明,该反应在热力学上是有利的,反应主要涉及三次C-C成键以及一次C-O断键:FeO分子与两分子C2H2相互作用并形成C-C键,产生中间体cyc-C4H4FeO;FeO活化第三分子C2H2,使其与cycC4H4FeO上的C原子成键,生成八元环中间体cyc-C6H6FeO;cyc-C6H6FeO上连接FeO的两个C原子成键,形成中间体C6H6OFe;中间体C6H6OFe的C-O断键,生成C6H6与FeO的分子复合物C6H6FeO。反应的转化频率(TOF)为6.73×10-9h-1,关键过渡态为第三次C-C成键过渡态,八元环中间体cyc-C6H6FeO是关键中间体。The reaction mechanism of the acetylene cyclotrimerization catalyzed by FeO molecule has been theoretically investigated in the gas phase at B3LYP/aug-cc-pvtz//6-311＋＋G（2d,2p） level. This catalytic reaction is thermodynamically favorable and in-volves the crucial reaction steps of C-C bond formation and C-O bond cleavage：（ 1 ） a six-member ring intermediate cyc-C4 H4 FeO formed from FeO center and two C2 H2 molecules;（ 2 ） the third C2 H2 molecule interacting with the cyc-C4 H4 FeO to generate the eight-member ring intermediate cyc-C6 H6 FeO;（ 3 ） C-C bond formation through the two C atoms connected with FeO in cyc-C6 H6 FeO to produce the benzene ring;（ 4 ） the C-O bond cleavage in C6 H6 OFe to form the molecular complex of FeO and ben-zene. The turnover frequency（TOF）is calculated to be 6. 73＆#215;10-9 h-1,with the third C-C bonding transition state as the TOF deter-mining transition state（TDTS）and cyc-C6H6FeO as the TOF determining intermediate（TDI）.

关 键 词：FeO分子 乙炔 苯 B3LYP 

分 类 号：O641.121[理学—物理化学]