• Regioselectivity in the [2 + 2] cyclo-addition reaction of triplet carbonyl compounds to substituted alkenes (Paterno-Büchi reaction): A spin-polarized conceptual DFT approach

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      https://www.ias.ac.in/article/fulltext/jcsc/117/05/0561-0571

    • Keywords

       

      Regioselectivity; cyclo-addition of triplet carbonyl compounds; spin-polarized conceptual DFT approach

    • Abstract

       

      Regioselectivity of the photochemical [2 + 2] cyclo-addition of triplet carbonyl compounds with a series of ground state electron-rich and electron-poor alkenes, the Paterno-Büchi reaction, is studied. Activation barriers for the first step of the triplet reaction are computed in the case of the O-attack. Next, the observed regioselectivity is explained using a series of DFT-based reactivity indices. In the first step, we use the local softness and the local HSAB principle within a softness matching approach, and explain the relative activation barriers of the addition step. In the final step, the regioselectivity is assessed within the framework of spin-polarized conceptual density functional theory, considering response functions of the system’s external potential v, number of electronsN and spin numberNs, being the difference between the number ofα andβ electrons in the spin-polarized system. Although the concept of local spin philicity, introduced recently within this theory, appears less suited to predict the regioselectivity in this reaction, the correct regioselectivity emerges from considering an interaction between the largest values of the generalized Fukui functionsfss on both interacting molecules.

    • Author Affiliations

       

      B Pintér1 F De Proft2 T Veszprémi1 P Geerlings2

      1. Inorganic Chemistry Department, Budapest University of Technology and Economics (BUTE), Szent Gellért tér 4, H-1521, Budapest, Hungary
      2. Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit, Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium
    • Dates

       
  • Journal of Chemical Sciences | News

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