The Chemistry of Indoles

Indole is a planar heteroaromatic molecule. The ten-electron pi system is formed by a pair of electrons from the nitrogen atom and eight electrons from the eight carbon atoms. Figures 1 through 3 depict the total atomic electron densities, the sigma atomic electron densities, and the pi electron densities, respectively, as obtained from self-consistent field molecular orbital calculations (193) which give dipole moments in excellent agreement with experimental values (23).