Quantum-chemical calculations of perfluoropropylene and perfluoroisobutylene by CNDO and INDO methods

Simulation of reactions of fluoroalkenes by quantum chemistry methods

“…Presumably, the substitution of the F atom is more probable. This assumption is in agreement with the results of calculations for other molecules (chlorotrifluoroethylene, in particular 20 ) and with the above-mentioned data on reactions of tribromofluoroethylene. 19 In addition, we believe that KFe(-CO) 2 Cp or Re(CO) 5 , in general, cannot be considered as classical nucleophiles.…”

“…In reactions with alcohols and thiols, the RO 7 (RS 7 ) group also adds to the carbon atom, which according to calculations 12 has a relatively high positive charge. A similar conclusion was derived 4,12,20 from calculations of 1,1-dichloro-2,2-difluoroethylene, chlorotrifluoroethylene, perfluoropropylene, and perfluoroisobutylene which is confirmed by the experimental data. The orientation of borane addition to monofluoroethylene according to calculations by the MNDO method, 25 is also in accordance with the experimental data (see also charges of fluoroalkenes calculated by the CNDO method 26 ).…”

“…Vinylic substitution (3) can be explained by a substantial increase in the polarity of the C ± F bond of the CF 2 group on going from tetrafluoroethylene to perfluoroisobutylene and chlorotrifluoroethylene. 20 Despite the fact that the negative charge on the fluorine atom is almost constant for all the four molecules considered, the positive charge on the carbon atom of the CF 2 group in perfluoropropylene, perfluoroisobutylene, and trifluorochloroethylene is substantially higher than in tetrafluoroethylene (Table 1).…”