Crystal structure of 5-tert-but­yl-10,15,20-tri­phenyl­porphyrin

In the title free base porphyrin, C(42)H(34)N(4), the neighbouring N⋯N distances in the center of the ring vary from 2.818 (8) to 2.998 (8) Å and the phenyl rings are tilted from the 24-atom mean plane at angles varying between 62.42 (2)–71.63 (2)°. The NH groups are involved in intra­molecular bifurcated N—H⋯(N,N) hydrogen bonds. The C(a)—C(m)—C(a) angles vary slightly for the phenyl rings, between 124.19 (18)–126.17 (18)°. The largest deviation from the mean plane of the 24-atom macrocycle is associated with the meso carbon at the substituted tert-butyl position, which is displaced from the mean plane by 0.44 (2) Å. The free base porphyrin is characterized by a significant degree of ruffled (B (1u)) distortion with contributions from domed (A (2u)) and wave [E(g)(y) and E(g)(x)] modes. In the crystal, mol­ecules are linked by a number of weak C—H⋯π inter­actions, forming a three-dimensional framework. The structure was refined as a two-component inversion twin.