2013. 54, 2 – UDC 541.6:546.26:547.17 GAS-PHASE REACTION OF THE ISOBUTENYL ANION WITH N2O FROM AB INITIO CALCULATIONS J.X. Liang1, Y.B. Wang1, Z.Y. Geng2, Y.Z. Wang2, Y.C. Wang2 1College of Chemical Engineering, Northwest University for Nationalities, Lanzhou, Gansu, P. R. China 2Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials; Ministry of Education, Northwest Normal University, Lanzhou, Gansu, P. R. China E-mail: wangyb16@yahoo.cn Received November, 23, 2011 Revised — January, 8, 2012 Calculations using conventional ab initio theory are performed to investigate the reaction mechanism associated with the gas-phase ion/molecule reaction of isobutenyl anion with N2O. <...> As a result, our theoretical findings strongly suggest that the main pathway is the reaction pattern of end-N attack and that the corresponding reaction mechanism basically relates to hydrogen migration, which may yield products cis-CH2(CH3)CCN2 , trans-CH2(CH3)CCN2 , and H2O. <...> Those are in good agreement with the experimental observations. <...> Moreover, based on the NBO, Activation Strain model and methyl group effect analysis, we also explored the characters of rate-determining step of the main pathway. <...> Keywords: isobutenyl anion, reaction mechanism, second-order Mшller—Plesset perturbation theory (MP2). <...> INTRODUCTION Carbanion, acting as a sort of valuable electron-rich reagent, plays a central role in organic chemistry because of its widespread synthetic utility [ 1 ]. <...> In many cases, it is a reactive nucleophilic intermediate [ 2—7] and is often encountered in organic chemistry, organometallic chemistry, alkyl lithium chemistry and so on [ 8—14]. <...> Many experiments have demonstrated that the stable carbanions, owing to charge delocalization, do exist [ 2—15]. <...> Previously, substantial efforts were made to gain and characterize carbanions experimentally [12—14 ], including bond strengths, [ 16 ] energies, [ 17 ] and resonance effects. [ 18 ] Also, the corresponding gas-phase reactions have been studied extensively. [ 11—13, 19, 20 ] Here, the work of Depuy et al. in 1977 [ 19 ] in which, using a flowing afterglow (FA <...>