EFFICIENT SYNTHESIS OF PHTHALOCYANINES AND RELATED MACROCYCLIC-COMPOUNDS IN THE PRESENCE OF ORGANIC-BASES

Various unsubstituted and substituted aromatic 1,2-dinitriles were converted in the presence of strong bases such as 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) in bulk reactions or an n-pentanol in high yields to metal-free phthalocyanines and related macrocyclic compounds. These efficient pathways, using commercially available bases, are easy to perform and work under relatively mild conditions. Bases weaker than DBU or DBN result in lower yield of phthalocyanines or impure products. Reactions in the presence of metal salts lead to metal phthalocyanines in yields similar to the metal-free analogues.