Intermolecular pi-stacking and F...F interactions of fluorine-substituted meso-alkynylporphyrin

Two C2-symmetric meso-alkynylporphyrins, namely 5,15-bis[(4-butyl-2,3,5,6-tetrafluorophenyl)ethynyl]-10,20-dipropylporphyrin, C(50)H(42)F(8)N(4), (I), and 5,15-bis[(4-butylphenyl)ethynyl]-10,20-dipropylporphyrin, C(50)H(50)N(4), (II), show remarkable pi-pi stacking that forms columns of porphyrin centers. The tetrafluorophenylene moieties in (I) show intermolecular interactions with each other through the F atoms, forming one-dimensional ribbons. No significant pi-pi interactions are observed in the plane of the phenylene and tetrafluorophenylene moieties in either (I) or (II). The molecules of both compounds lie about inversion centers.