Neighboring group’s effect in sigmatropic migration on indol rings. A theoretical study and NBO analysis

Structural properties, energies behavior and NBO analysis was performed for1-5 prototrophic shift endinel boran where substitutions like H, CH3 and CF3 that were placed on Benzene were investigated by using DFT-B3LYP/6-311+G** level of theory. The Results show that, -BH2 shift doesn’t take place and a kind of [1,3] shift for borotrophic occured. In prototrophic shift, however, [1,5] transition easily happened. The Results of calculations using B3LYP, HF and MP2 [basic seyies 6-311+G**] show that Ea for CF3 substitutionis is lower than H substitution; also, this amount of activation energy for CH3 was lower than CF3. But for prototrophic shift, activation energy changes, as will be shown in the following CF3, H and CH3 tables. Finally, prototrophic shift activation energy in proportion to that of borotrophic shift is higher. Lower amount of activation energy in bortorphic shift show that rotation of bore on the cycle can happen in the ambient temperature.