Efficient synthesis of 2-oxy-5,10,15,20-tetraphenylporphyrins from a nitroporphyrin by a novel multi-step cine-substitution sequence

Abstract

(2-Nitro-5,10,15,20-tetraphenylporphyrinato)copper(II)(1) reacts with sodium benzylate or sodium methoxide in dimethylformamide by a novel aromatic nucleophilic substitution-nucleophilic addition sequence in which hydrogen is the leaving group to give the corresponding 2,2-dialkoxy-3-dihydroporphyrins which are efficiently converted into 2-alkoxyporphyrins in two steps; the overall sequence accomplishes a cine-substitution.