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

• Simple and effective procedure afforded Zn meso-aryltetrabenzotriazaporphyrin.
• The compound tends to form compact H-aggregates in solution.
• Meso-substituted tetrabenzotriazaporphyrin was firstly studied by XRD.
• Structural features of the compound and Zn phthalocyanine were compared.
• Meso-substituent favors structural ordering and enhancement of π–π interactions.

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.

X-ray crystal structure of a meso-substituted tetrabenzotriazaporphyrin has been obtained and investigated for the first time.Figure optionsDownload as PowerPoint slide