• Rezan Jalal Salahaddin University-Erbil, Erbil, Iraq
  • Hassan Abdallah Salahaddin University, Iraq




Dimerization, DFT, 3-heteroaryl-acrylates, [2 2] cycloaddition


Photochemical dimerization reactions provide an efficient approach to the synthesis of complex cyclobutene containing structures, which are often difficult to obtain by reactions of another type. Industrially, the photochemical healing of polymers proceeds successfully and very fast via [2+2] photocycloaddition. It is assumed that the heterocyclic ring has a great influence on the regioselectivity and stereoselectivity of photochemical dimerization of various heteroaryl acrylates. A detailed explanation of the observed photochemical reaction of different 3-heteroaryl(furyl, thiophyl, selenophyl and tellurophyl)-acrylates is furnished theoretically on the basis of a comprehensive review of the photochemical dimerizations of this type of compounds. Density functional theory (DFT) was used to study the reaction mechanism and locate all the intermediates and transition states along the potential energy curve. The calculated energy barriers were used to compare the stability of different conformations. The reactions showed good regio- and stereoselectivity through the formation of biradical transition state. The global electrophilicity, nucleophilicity, hardness, softness and ionization potential were evaluated to rationalize the results of the most stable isomers. In addition, IR vibration frequencies, energetic parameters and molecular orbital analysis were analyzed for the most stable products.


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