Efficient Synthesis of Hangman Porphyrins

A two-step synthetic method has been designed to furnish hangman porphyrins in good yields from easily available starting materials. The use of the microwave irradiation technique has been found to be valuable for delivering the carboxylic acid hanging group in a much simplified and less time-consuming basic ester hydrolysis (4 h vs 7 days under harsh acidic conditions). The new route facilitates the synthesis of various hangman porphyrins that previously had limited or no access.