(4n +2)π Huckel’s rule of Bn NnC(8-2n) H8 as anti-cancer heterocyclic systems

• Neda SamieiSoofi Universidad del Zulia
• Majid Monajjemi Department of Chemical Engineering, Central Tehran Branch, Islamic Azad University

Resumen

Replacing of Boron and nitrogen atoms in [8] annulene molecule help us for explaining the details of mentioned magnetic mechanism concerning the ring currents of the carbon disappearing in the isoelectronic azabora-hetero-cycles variants (B_n N_n C_(8-2n) H₈^2-,n=0,1,2,3 and4  The (4n+2)  systems aromatic on variants of BnNnC(8-2n) H8 (n=0, 1 ,2,3 and 4) via the localized orbital by considering   the current density induced have been studied. It has been predicted a four-electron dia-tropic (aromatic) ring current for (4n+2)  aza-bora-hetero-cycles variants of BnNnC (8-2n) H8(n=0,1 ,2,4) and a two-electron para-tropic (anti-aromatic) current for (4n) . HOMO and LUMO energies and also HOMO/LUMO overlapping in whole space have been calculated. Two forms can be considered, first the HOMO–LUMO transition leads to a para-tropic contribution, and second HOMO–LUMO+1 transitions to the dia-tropic contributions. In addition, the NICS and SNICS values confirm the amounts of aromaticity and anti-aromaticity in those rings.

Citas

Andrés, J.L., Castaño, O., Morreale, A., Palmeiro, R., Gomperts, R (1998). Potential energy surface of cyclooctatetraene. J Chem Phys 108, 203–207.

Anet, F.A.L., O’Leary, D.G., (1992). The shielding tensor. Part II: Concepts Magn. Reson. 4, 35

Bader, R.F.W. (1990). Atoms in Molecule: A quantum Theory (Oxford Univ. press, Oxford.

Besler, B.H., Merz, K.M., Kollman, P.A (1990). Atomic charges derived from semi empirical methods J. comp. Chem (11): 431-439, DOI: 10.1002/jcc.540110404

Chirlian, L.E., Francl, M.M (1987). Atomic charges derived from electrostatic potentials: A Detailed study. J.comp.chem (8): 894-905, DOI: 10.1002/jcc.540080616

Daudel, R., Lefebvre, R., Moser, C., (1959). Quantum Chemistry, Methods and Applications, Wiley-Interscience, New York, p. 449.

Gellini, C., Salvi, P. R. (2010). Structures of Annulenes and Model Annulene Systems in the Ground and Lowest Excited States. Symmetry 2, 1846–1924.

Hrovat, D.A., Borden, W.T (1992). CASSCF calculations find that D8h geometry is the transition state for double bond shifting in cyclooctatetraene. J Am Chem Soc 114: 5879–5881.

Haeberlen, U. (1976). In Advances in Magnetic Resonance, Suppl. 1 Academic Press, New York. M. Mehring. M, Principles of High Resolution NMR in Solids, 2nd.ed, Springer Verlag, Berlin.

Kohn, W., Sham, L.J. (1965). Self-Consistent Equations Including Exchange and Correlation Effects. Phys. Rev (140) A: 1133-1138

Longuet-Higgins, H.C., (1967). in Aromaticity, Special Publication No. 21, The Chemical Society, London, 109 –110.

Lu, T., Chen, F., (2012). Quantitative analysis of molecular surface based on improved Marching Tetrahedra algorithm, J. Mol. Graph. Model (38): 314-323

Martin, F., Zipse, H., (2005). Charge distribution in the water molecule--a comparison of methods. J Comp Chem. (26): 97 – 105

Monajjemi, M., Lee, VS., Khaleghian, M., Honarparvar, B., Mollaamin, F., (2010). Theoretical Description of Electromagnetic Nonbonded Interactions of Radical, Cationic, and Anionic NH2BHNBHNH2 Inside of the B18N18 Nano ring. J. Phys. Chem. C (114) 15315

Monajjemi, M., Khaleghian, M., (2011). EPR Study of Electronic Structure of [CoF6] and B18N18 Nano Ring Field Effects on Octahedral Complex. J Clust Sci (22):673–692 DOI 10.1007/s10876-011-0414-2

Monajjemi, M. (2012). Quantum investigation of non-bonded interaction between the B15N15 ring and BH2NBH2 (radical, cation, anion) systems: a nano molecular motor, Struct. Chem. (23): 551

Nishinaga, T., Ohmae, T., Iyoda, M. (2010). Recent Studies on the Aromaticity and Antiaromaticity of Planar Cyclooctatetraene. Symmetry 2, 76–97.

Naor, R., Luz, Z., (1982). Bond Shift Kinetics in Cyclo -Octatetraene by Dynamic NMR in Liquid Crystalline Solvents. The Journal of Chemical Physics 76, 5662–5664.

Perdew, J. P., Burke, K., Ernzerhof (1996). Generalized Gradient Approximation Made Simple. Phys. Rev. Lett. (77): 3865-3868

Schild, A., Paulus ,B., (2013). Multireference calculations for ring inversion and double bond shifting in cyclooctatetraene. J Comput Chem 34:1393–1397.

Stevenson, C.D., Brown, E.C., Hrovat, D.A, Borden, W.T (1998). Isotope effects on the ring inversion of cyclooctatetraene. J Am Chem Soc 120:8864–8867.

Streitwieser, A. Jr. (1961). Molecular Orbital Theory for Organic Chemists, Wiley, New York, 1; b) N. C. Baird, M. A. Whitehead, Can. J. Chem. 1966, 44, 1933 –1943.

Wenthold, P.G., Hrovat, D.A., Borden, W.T., Lineberger, W.C. (1996). Transition-state spectroscopy of cyclooctatetraene. Science 272:1456–1459.

Yoshida, T., Tokizaki, C., Takayanagi, T., (2015). Theoretical Analysis of the Transition-State Spectrum of the Cyclooctatetraene Unimolecular Reaction: Three Degree-of Freedom Model Calculations. Chem. Phys. Lett., 634, 134−139.

Willstätter, R., Waser, E (1911). "Über Cyclo-octatetraen" [On cyclooctatetraene]. Ber. Dtsch. Chem. Ges.44 (3): 3423–3445. doi:10.1002/cber.191104403216.

Willstätter, R., Heidelberger, M., (1913). Zur Kenntnis Des Cyclo-Octatetraens. Chem. Ber. 46, 517–527.

Wu, J. I., Fernández, I., Mo, Y., Schleyer, P. V. R. (2012). Why Cyclooctatetraene Is Highly Stabilized: the Importance of “Two-Way” (Double) Hyperconjugation. J. Chem. Theory Comput. 8, 1280–1287.