Face to face porphyrins as synthetic host molecules

Article abstract of DOI:10.1016/S0040-4020(01)90379-5

The bis-zincporphyrins 9 and 11 were prepared from the bis-(3′-hydroxyphenyl)-porphyrin 6. Both bis-zincporphyrins formed complexes in CHCl₃ with a variety of amines and showed a strong preference for diamines, such as H₂N(CH₂)nNH₂ and 4,4′-dipyridyl. The limited degree of chain length recognition for the diamine guests by both hosts is associated with conformational flexibility of both host and guest but the rigid guest, 4,4′-dipyridyl, is selectively complexed through operation of the chelate effect.