Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9590550 | Journal of Molecular Structure: THEOCHEM | 2005 | 9 Pages |
Abstract
Ab initio HF/6-31G*, B3LYP/6-31G* and MP2/6-31G*//HF/6-31G are employed for calculations of equilibrium constants (Keq), rate constants (kr), activation electronic energies (ÎE#), enthalpies (ÎH#), and Gibbs free energies (ÎG#) for conversions of 3(X)-1H-azepine, 1 (where X=H, NH2, OCH3, CH3, CF3, F, Cl, Br, NO2 and CN) to their corresponding 2(X)-benzene imines, 2 (Series 1). The same calculations are carried out for conversions of 4(X)-1H-azepines, 1â², to analogous 3(X)-benzene imines, 2â² (Series 2). Equilibriums related to Series 1 with different (X) substitutions occur with Keqs=1.4Ã107 (H), 4.8Ã104 (NH2), 5.6Ã103 (OCH3), 9.7Ã105 (CH3), 1.1Ã107 (CF3), 3.1Ã105 (F), 7.6Ã105 (Cl), 1.2Ã106 (Br), 2.4Ã108 (NO2) and 2.4Ã106 (CN). Similarly, for Series 2, the Keqs are: 1.4Ã107 (H), 7.1Ã107 (NH2), 9.7Ã106 (OCH3), 9.4Ã106 (CH3), 3.0Ã107 (CF3), 9.6Ã107 (F), 7.1Ã107 (Cl), 9.3Ã107 (Br), 1.0Ã109 (NO2) and 1.2Ã108 (CN). A Hammet Ï value of 1.70 is obtained for Series 2. Due to steric effects, meaningful Ï is not fond for Series 1.
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Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
M.Z. Kassaee, S. Arshadi, B.N. Haerizade, E. Vessally,