First X-ray crystallographic study of a meso-substituted tetrabenzotriazaporphyrin: Structural effect of a meso-aryl unit on 27-(2-methylphenyl)tetrabenzotriazaporphyrinato zinc example in comparison with zinc phthalocyaninate

Article abstract of DOI:10.1016/j.dyepig.2014.02.012

A recently developed synthetic procedure afforded meso-aryl substituted tetrabenzotriazaporphyrin complex, namely 27-(2-methylphenyl)tetrabenzo[b,g,l,q] [5,10,15]triazaporphyrinato zinc (^2-MePhTBTAPZn, 1). The reaction also produced zinc phthalocyanine (PcZn, 2) as a byproduct. The complexes were characterized by the UV-Vis, NMR spectroscopy as well as MALDI-TOF mass spectrometry. Furthermore, they form supramolecular structures [1·DMSO]·2(DMSO) (I) and [2·DMSO]·0.65(DMSO) ·0.5(CH₃OH) (II) determined by single-crystal X-ray diffraction analysis. To the best of our knowledge, I represents the first X-ray defined structure of a meso-substituted TBTAP derivative. Both structures were shown to be composed of centrosymmetric dimers, which are stabilized by the axial π-stacking intermolecular interactions. Comparison of the data for I and II indicates that the presence of the meso-aryl substituent in the TBTAP molecule results in considerable and even unexpected structural effects.