Theoretical Survey of the Gas-Phase Reactions of Allylamine with Co+

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• 作者：Yan Ma ; Wenyue Guo ; Lianming Zhao ; Songqing Hu ; Jun Zhang ; Qingtao Fu ; Xiangfeng Chen
• 刊名：Journal of Physical Chemistry A
• 出版年：2007
• 出版时间：July 19, 2007
• 年：2007
• 卷：111
• 期：28
• 页码：6208 - 6216
• 全文大小：585K
• 年卷期：v.111,no.28(July 19, 2007)
• ISSN：1520-5215

文摘

Density functional theory calculations have been carried out to survey the gas-phase reactions of allylaminewith Co⁺. The geometries and bonding characteristics of all the stationary points involved in the reactionshave been investigated at the B3LYP/6-311++G(d,p) level. Final energies are obtained by means of theB3LYP/6-311+G(2df,2pd) single-point calculations. The performance of these theoretical methods is valuatedwith respect to the available thermochemical data. Co⁺ strongly binds allylamine by forming a chelated structurein which the metal cation binds concomitantly to the two functional groups of the neutral molecule. Variousmechanisms leading to the loss of NH₃, NH₂, C₂H₂, and H₂ are analyzed in terms of the topology of thepotential energy surface. The most favorable mechanism corresponds to the loss of NH₃, through a processof C-N activation followed by a concerted mages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-H shift. The accompanying NH₂ elimination is also discussed.The loss of C₂H₂ is also favorable, through C-C activation and stepwise mages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-H shift, giving Co⁺(NH₂CH₃) andCo⁺H(NH₂CH₂) as the product ions. Various possible channels for the loss of H₂ are considered. The mostfavorable mechanism of the H₂ loss corresponds to a pathway through which the metal acts as a carrier,connecting a hydrogen atom from the methylidyne group of allylamine with a hydrogen atom of the terminalmethylene group. The product ion of this pathway has a tricoordinated structure in which Co⁺ binds to theterminal two Cs and N atoms of the NH₂CH₂CCH moiety.