Abstract
Selective nitration of tetraphenylporphyrin (TPP) and its derivatives is reported. The reaction of meso-aryl substituted porphyrins with fuming yellow nitric acid (d = 1.53) at the temperature 0–20°C results in the formation of 5,10-bis(4-nitroaryl)-15,20-diarylporphyrins with yields of 30–83%.