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The [3+2] cycloaddition (32CA) reaction of an azomethine ylide (AY) with an electrophilic ethylene linked to triazole and ferrocene units has been studied within the Molecular Electron Density Theory (MEDT) at the <i>ω</i>B97X-D/6-311G(d,p) level. The topology of the electron localization function (ELF) of this AY allows classifying it as a <i>pseudo(mono)radical</i> species characterized by the presence of two monosynaptic basins, integrating a total of 0.76 e, at the C1 carbon. While the ferrocene ethylene has a strong electrophilic character, the AY is a supernucleophile, suggesting that the corresponding 32CA reaction has a high polar character and a low activation energy. The most favorable <i>ortho</i>/<i>endo</i> reaction path presents an activation enthalpy of 8.7 kcal·mol⁻¹, with the 32CA reaction being exergonic by −42.1 kcal·mol⁻¹. This reaction presents a total <i>endo</i> stereoselectivity and a total <i>ortho</i> regioselectivity. Analysis of the global electron density transfer (GEDT) at the most favorable <b>TS-on</b> (0.23 e) accounts for the high polar character of this 32CA reaction, classified as forward electron density flux (FEDF). The formation of two intermolecular hydrogen bonds between the two interacting frameworks at the most favorable <b>TS-on</b> accounts for the unexpected <i>ortho</i> regioselectivity experimentally observed.