Trans A2B2 Porphyrins: Synthesis, Crystal Structure Determinations and Hirshfeld Surface Analysis

Abstract

AbstractTrans‐A2B2 porphyrins containing p‐methoxyphenyl (A)/p‐methylphenyl (B) (P4) and p‐chlorophenyl (A)/p‐methylphenyl (B) (P5) at the four meso (−CH=) positions of the tetrapyrrolic macrocycles have been synthesized by employing the two steps modified Adler's methodology. Remarkably, the present synthetic scheme afforded us the needle shaped single crystals of (P4) and (P5) that helped us investigate the three dimensional structural architectures of the prepared Trans‐A2B2 porphyrins. Hirschfeld surface analysis (HSs) was used to visualize the fidelity of the crystal structures of (P4) and (P5). This method permitted the identification of individual types of intermolecular contacts and their impact on crystal packings. Molecules are linked by a combination of H⋅ ⋅ ⋅H and C⋅ ⋅ ⋅H contacts, which have clear signatures in the corresponding fingerprint plots. The effect of incorporating two different non sterically demanding functionalities at the para positions of meso phenyl rings on the optical and thermal properties of symmetric (A4) porphyrins i. e. Tetra‐para‐methoxy phenyl porphyrin P1, Tetra‐para‐methyl phenyl porphyrin P2 and Tetra‐para‐chloro phenyl porphyrin P3, have been investigated and the results have been discussed in detail.