title: Cyclic π electron delocalization in fluoroborazines.
abstract: How does the most electronegative atom, fluorine, affect cyclic π electron delocalization (aromaticity) of an inorganic counterpart of benzene, borazine? Previous studies have shown that N-fluorination decreases the aromatic character, whereas conclusions about the effect of B-fluorination oppose each other ( J. Phys. Chem. A 1997 , 101 , 9410 and J. Mol. Struct.: THEOCHEM 2005 , 715 , 91 ). The aim of this study is to resolve this discrepancy and also to evaluate a degree of cyclic π electron delocalization in all possible polyfluoroborazines. This was done by employing four aromaticity indices, HOMA, NICS, ECRE, and PDI. NICS, ECRE, and PDI gave a satisfactory description of aromaticity of the studied molecules. It was found that N-monofluoroborazine, N-difluoroborazine, and N-trifluoroborazine are the only fluorinated derivatives that exhibit a higher degree of aromaticity compared to borazine. This result opposes the previous ones regarding the influence of N-fluorination.
authors.affiliation: Faculty of Chemistry, University of Belgrade , Studentski trg 16, P.O. Box 158, 11000 Belgrade, Serbia.
authors.forename: Marija
authors.initials: M
authors.lastname: Baranac-Stojanović