Synthesis under high hydrostatic pressure - a new method to prepare 5,10,15,20-tetrakis[4-(substituted amino)-2,3,5,6-tetrafluorophenyl]porphyrins

Abstract

5,10,15,20-Tetrakis(pentafluorophenyl) porphyrin reacts with primary alkylamines and heterocyclic amines, at 50 degrees C and under high pressure (450 MPa), to produce the N-substituted tetraamino derivatives in high yields. Under similar conditions, the reaction with the bulky dibutylamine and dipentylamine affords the corresponding mono-substituted dialkylaminoporphyrins in 10% yield. This new protocol arises as a considerable improvement of the methods already known, which usually require high temperatures and are not effective when using secondary amines having long alkyl groups.