Key points are not available for this paper at this time.
Tetrakisarylporphyrins are conveniently chlorosulphonated in high yields.These chlorosulphonyl compounds may he converted in high yield into sulphonic acid derivatives through reaction with a variety of nucleophiles so as to give, for example, the free sulphonic acid, a sulphonamide or a sulphonate ester.
Johnstone et al. (Mon,) studied this question.