Hamzehloueian Mahshid, Hosseinzadeh Rahman, Ghandiyar Setayesh
Department of Chemistry, Jouybar Branch, Islamic Azad University, Jouybar, Iran.
Department of Organic Chemistry, Faculty of Chemistry, University of Mazandaran, Babolsar, 47416, Iran.
J Mol Graph Model. 2020 Jun;97:107552. doi: 10.1016/j.jmgm.2020.107552. Epub 2020 Jan 28.
A density functional theory study was performed on the mechanism and site selectivity of a domino [3 + 2] cycloaddition/retro-Diels-Alder reaction between benzyl azide and 7-oxabicyclo [2.2.1]hepta-2,5-diene-2,3-dicarboxylate (oxanorbornadienedicarboxylate) which provide a stable 1,2,3-triazole and the results were compared with the click reaction between benzyl azide and dimethyl acetylenedicarboxylate (DMAD) with similar triazole product. Parr functions analysis, hard and soft acids and bases (HSAB) principle and potential energy surface analysis were utilized for studying the site selectivity of this reaction, and the results are consistent with the experimental observations. The molecular mechanisms of these reactions were established by electron localization function (ELF) and noncovalent interactions (NCI) topological analysis. ELF topological patterns indicated a two-stage one-step mechanism for the 32CA reaction and NCI analysis displayed the noncovalent interactions which are responsible for the preferred path.
对苄基叠氮化物与7-氧杂双环[2.2.1]庚-2,5-二烯-2,3-二羧酸酯（氧杂降冰片二烯二羧酸酯）之间的多米诺[3 + 2]环加成/逆狄尔斯-阿尔德反应的机理和位点选择性进行了密度泛函理论研究，该反应生成一种稳定的1,2,3-三唑，并将结果与苄基叠氮化物与二甲基乙炔二羧酸酯（DMAD）生成类似三唑产物的点击反应进行了比较。利用帕尔函数分析、软硬酸碱（HSAB）原理和势能面分析来研究该反应的位点选择性，结果与实验观察一致。通过电子定位函数（ELF）和非共价相互作用（NCI）拓扑分析确定了这些反应的分子机理。ELF拓扑模式表明32CA反应为两步一步机理，NCI分析显示了负责优先路径的非共价相互作用。
