title: 2,3,12,13-Tetrabromo-5,10,15,20-tetrakis(4-butoxyphenyl)porphyrin 1,2-dichloroethane solvate.
abstract: Nonmesogenic 2,3,12,13-tetrabromo-5,10,15,20-tetrakis(4-butoxyphenyl)porphyrin crystallizes as the title 1,2-dichloroethane solvate, C(60)H(58)Br(4)N(4)O(4) x C(2)H(4)Cl(2). The porphyrin ring shows a nonplanar conformation, with an average mean plane displacement of the beta-pyrrole C atoms from the 24-atom (C(20)N(4)) core of +/-0.50 (3) A. The 1,2-dichloroethane solvent is incorporated between the porphyrin units and induces the formation of one-dimensional chains via interhalogen Cl...Br and butyl-aryl C-H...pi interactions. These chains are oriented along the unit-cell a axis, with the macrocyclic ring planes lying almost parallel to the (010) plane. The chains are arranged in an offset fashion by aligning the butoxy chains approximately above or below the faces of the adjacent porphyrin core, resulting in decreased interporphyrin pi-pi interactions, and they are held together by weak intermolecular (C-Br...pi, C-H...pi and C-H...Br) interactions. The nonplanar geometry of the macrocyclic ring is probably due to the weak interporphyrin interactions induced by the solvent molecule and the peripheral butoxy groups. The nonplanarity of the mesogens could influence the mesogenic behaviour differently relative to planar porphyrin mesogens.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Madras, Chennai 600 036, India. byra@iitm.ac.in
authors.forename: P
authors.initials: P
authors.lastname: Bhyrappa
authors.forename: C
authors.initials: C
authors.lastname: Arunkumar
authors.forename: B
authors.initials: B
authors.lastname: Varghese