Electronic absorption spectra of some substituted indoles

Abstract The electronic absorption spectra of 4-chloro-, 5-chloro-, 5-methyl-, 6-methyl- and 5-methoxy indoles have been recorded. The observed spectra lying in the region λ3100 A to λ 2650 A has been identified as a π* ← π transition analogous to the λ 2850 A system of indole. The results are reported and discussed in this paper.