13C NMR spectra of substituted phenazines: Substituent effects on carbon‐13 chemical shifts and the use of 13C15N coupling constants for the assignment of the aromatic carbons

Abstract The 13 C NMR spectra of 19 substituted phenazines have been measured. Substituent increments of the chemical shifts were calculated for methoxy, carbomethoxy and methyl derivatives. 15 N‐Enriched phenazines were synthesized and n J ( 13 C 15 N) values were used for the assignment of the signals of the aromatic carbons.