13C NMR spectra of thiophenes. III—Bromothiophenes

The ¹³C 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 the ¹³C chemical shifts. The substituent effect on various types of ¹³C, ¹H coupling constants is also obtained and discussed.