13C NMR studies of substituted 2,3-diphenylindoles. Methyl and nitro derivatives

The ¹³C nmr spectra of a series of methyl- and/or nitro-2,3-diphenylindole derivatives are reported. The dependence of a) ¹H and ¹³C methyl group shieldings on molecular geometry and b) the possibility that ¹³C nmr might be a useful tool in determining photochemical reactivity are discussed briefly.