Potential energy diagrams benzene

Figure 15-20 Potential-energy diagram describing the course of the reaction of benzene with an electrophile. The first transition state is rate determining. Proton loss is relatively fast. The overall rate of the reaction is controlled by EaJ the amount of exothermic energy released is given by AH°.

The form of potential energy curve deduced by Olah from kinetic evidence on the nitration of benzene, and some alkyl- and halo-benzenes, by nitronium ions derived from NOJ BIV is shown in Fig. 18. In this diagram, position D is associated with a localized structure analogous to that of Fig. 16 and 19b. 

Sketch potential-energy/reaction-coordinate diagrams for the two propagation steps of the monobromination of benzene (Problem 24). 

It was demonstrated that in the case of benzene oxidation, the intrinsic reactivities of all potential extra-framework complexes for benzene activation, the initial dissociation of N O, and the final phenol formation were very similar. The eneigetics of elementary reactions steps were influenced only sUghtly by the nature and the structural properties of the catalytic site. Representative reaction energy diagrams for the mononuclear Fe + and Fe sites are shown in Fig. 8. 

Fio. 19. Comparison of the two lowest adiabatic ionization potentials in benzene with the three lowest in pyrrole and furan. The values arranged as an energy level diagram were obtained by photoelectron spectroscopy. (T, N. Badwan and D. W. Turner, unpublished work.)... 

Y. 1. Aristov, V. N. Parmon, G. Cacciola, N. Giordano, High-temperature chemical heat pump based on reversible catalytic reactions of cyclohexane-dehydro-genation/benzene-hydrogenation Comparison of the potentialities of different flow diagrams, Int.J. Energy Res. 1993, 17,293-303. 

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