Semiempirical studies on the transition structure of the Baeyer and Villiger rearrangement. The reaction of acetone with alkyl and aryl peracids
Por:
Cádenas R., Reyes L., Lagúnez-Otero J., Cetina R.
Publicada:
1 ene 2000
Resumen:
The mechanism of Baeyer-Villiger reaction with substituted peracids is analyzed by determining with semiempirical (AMI and PM3) methods, the Mulliken charges, structures, energies, and the evolution of bond orders. A significant correlation was found between the bond order and the activation energy as well as with the charge and the activation energy. Elliptical coordinates were extensively used, finding correlation between the energy of activation and the parallel, antisymmetric coordinates, and eccentricity. The latter was also correlated with the shift of bond order. The geometries of the Criegee intermediate, the methyl group migration transition state structure (TSs), and the product were found and optimized. As in our previous work, we find that the topology of the TSs is invariant. By using elliptic coordinates we can also observe that the atoms constituting three reactive circuits are found on ellipsoidal surfaces where the reactive centers are the foci. The relationship between the energy of activation and the Hammett electronic constant of each of the substituents is presented. (C) 2000 Elsevier Science B.V.
Filiaciones:
Cádenas R.:
Instituto De Química, Universidad Nacional Autónoma De Mexico, Ciudad Universitaria, Circuito, Exterior, 04510 Coyoacan, Mexico
Reyes L.:
Facultad De Química, Universidad Nacional Autónoma De Mexico, Ciudad Universitaria, Circuito, Exterior, 04510 Coyoacan, Mexico
Lagúnez-Otero J.:
Instituto De Química, Universidad Nacional Autónoma De Mexico, Ciudad Universitaria, Circuito, Exterior, 04510 Coyoacan, Mexico
Cetina R.:
Instituto De Química, Universidad Nacional Autónoma De Mexico, Ciudad Universitaria, Circuito, Exterior, 04510 Coyoacan, Mexico
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