Density Functional Study on [3+2]-Dipolar Cycloaddition Reaction of the N-heterocyclic Carbene Boryl Azide with Olefins

E-mail: zhxh135@126.comReceived November 11, 2013, Accepted January 18, 2014The cycloaddition reactions of the N-heterocyclic carbene boryl azide with methyl acrylate, butenone, andhexafluoropropene have been investigated theoretically. Solvent effects on these reactions have been exploredby calculation that included a polarizable continuum model (PCM) for the solvent (C6H6). The title reactioncould produce 4- and 5-substituted 1,2,3-triazolines, respectively. The reaction systems have the higherchemical reactivity with the low barriers and could be favored. Yet the smaller differences have been found tooccur in energetics, and the cycloaddition reactions occur for s-trans conformations over s-cis conformations.The calculations indicated that the cycloaddition reaction of the alkenes have certain regioselectivity.Key Words : Cycloaddition reaction, Boryl azide, Olefin, Density functional studyIntroductionN-Heterocyclic carbenes (NHCs) are widely used Lewisbases and boranes are popular Lewis acids.