Synthesis and characterisations of non-covalently bound aniline–indium(III) porphyrins

Abstract

The aniline–indium(III) porphyrin chromophoric systems in which aniline is bonded non-covalently with porphyrin macrocycles were obtained by the treatment of each of the indium(III) porphyrins, i.e. tetra-p-methoxyphenyl indium(III) porphyrin and tetra-p-chlorophenyl indium(III) porphyrin with neutral aniline in CHCl3/CH3OH mixtures. The prepared aniline–indium(III) porphyrin chromophoric systems were successfully characterised by using FT-IR spectroscopy, 1H NMR spectroscopy and ESI-mass spectrometry. The 1H NMR and UV–Visible absorption spectroscopic studies of aniline–indium(III) porphyrin systems were further recorded as a function of pure aniline concentration in proper solvents. The results of these spectroscopic studies indicate the existence of interchromophoric interactions between aniline and indium(III) porphyrins which increase with the increase in pure aniline concentrations. Powder X-ray diffraction (PXRD) measurement data reflects change in crystalline phases of parent complexes upon incorporation of aniline molecules. Thermogravimetric analysis (TGA) indicates that aniline-incorporated indium(III) porphyrins are less thermally stable than their parent complexes.