Institut Charles Gerhardt, Université Montpellier 2, CNRS 5253, case courrier 1501, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France.
J Comput Chem. 2012 Jul 30;33(20):1689-700. doi: 10.1002/jcc.22999. Epub 2012 Apr 27.
A detailed analysis of the reaction profiles of the hydroamination reaction between ethylene and ammonia catalyzed by the diplatinum(II) [{Pt(NH(2))(μ-H)(PPh(3))}(2)] complex is presented herein using density functional theory computational techniques. The coordinatively unsaturated 14e T-shaped [Pt(NH(2))(PPh(3))H] species resulted from the dissociation of the diplatinum [{Pt(NH(2))(μ-H)(PPh(3))}(2)] precatalyst are identified as the active catalytic species. All possible reaction pathways that constitute the entire catalytic cycle have exhaustively been investigated. Overall, the rate-determining step of all catalytic cycles constructed was found to be the oxidative addition of ammonia that leads to the regeneration of the catalyst. According to the energy span model, the outer-sphere mechanism for the hydroamination of ethylene with ammonia catalyzed by the diplatinum complexes is favored over the inner-sphere one, whereas TOF values are in favor of the inner-sphere mechanism.
本文采用密度泛函理论计算技术，对乙烯与氨的加氢胺化反应在双铂（II）[{Pt（NH（2））（μ-H）（PPh（3））}（2）]配合物催化下的反应历程进行了详细分析。配位不饱和的 14e T 型[Pt（NH（2））（PPh（3））H]物种是由双铂[{Pt（NH（2））（μ-H）（PPh（3））}（2）]前催化剂的解离产生的，被确定为活性催化物种。所有可能的反应途径都被彻底研究过了。总的来说，所有构建的催化循环的速率决定步骤是氨的氧化加成，这导致催化剂的再生。根据能隙模型，双铂配合物催化乙烯与氨的加氢胺化的外球机理比内球机理更有利，而 TOF 值则有利于内球机理。
