Supramolecular complexes of carboxy-substituted zinc porphyrinates with triethylenediamine

Abstract

α,α-and α,β-Atropoisomers of zinc 5,15-bis(2-carboxyphenyl)octaalkylporphyrinate were obtained, and their complex formation with triethylenediamine in toluene was studied. The α,α-atropoisomer is present in the solution as a supramolecular dimer and forms a 1:1 complex with the two-centered nitrogen-containing base. The complex formation of the undimerized α,β-atropoisomer with triethylenediamine can give 2:1 or 1:1 complexes, depending on the reagent ratio. The stability constants of the complexes and the concentration ranges of their formation were determined by means of spectrophotometric titration and 1H NMR spectroscopy.