AbstractThe13C NMR spectra of all bromo substituted thiophenes have been obtained at 15·085 MHz.13C signal assignments for monobromothiophenes have been confirmed by comparison with the spectra of their partially deuteriated derivatives; a revision is made for the assignment in 3‐bromothiophene. The substituent effect of bromine is generally additive for the13C chemical shifts. The substituent effect on various types of13C,1H coupling constants is also obtained and discuss