Kinetics of ionization of CH bonds of five-membered heterocycles and their benzo derivatives and mechanism of the elementary act of proton transfer. 1. Quantum-chemical calculation of geometrical and electron structures of the molecules and carbanions
The heats of formation and the parameters of the geometrical and electron structures of the molecules and carbanions of furan, thiophene, N-methylpyrrole, N-methylimidazole, benzofuran, benzothiophene, N-methylindole, benzene, and naphthalene were calculated by the self-consistent-field (SCF) MO LCAO method within the MNDO and CNDO/2 approximations. According to the calculations, the deprotonation of the indicated CH acids leads to relatively small changes in the geometrical structures of the anionic fragments. The charge on the deprotonated carbon atom changes most markedly in the formation of the carbanions.
KeywordsNaphthalene Thiophene Furan Proton Transfer Geometrical Structure
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