Tri-fluoro-methane-sulfonate salt of 5,10,15,20-tetra-kis-(1-benzyl-pyridin-1-ium-4-yl)-21,23-porphyrin and its Ca complex.

The synthesis, crystallization and characterization of a tri-fluoro-methane-sulfonate salt of 5,10,15,20-tetra-kis-(1-benzyl-pyridin-1-ium-4-yl)-21,23-por-phy-rin, CHN ·4CFSO ·4HO, ·OTf, are reported in this work. The reaction between 5,10,15,20-tetra-kis-(pyridin-4-yl)-21,23-porphyrin and benzyl bromide in the presence of 0.1 equiv. of Ca(OH) in CHCN under reflux with an N atmosphere and subsequent treatment with silver tri-fluoro-methane-sulfonate (AgOTf) salt produced a red-brown solution. This reaction mixture was filtered and the solvent was allowed to evaporate at room temperature for 3 d to give ·OTf. Crystal structure determination by single-crystal X-ray diffraction (SCXD) revealed that ·OTf crystallizes in the space group 2/. The asymmetric unit contains half a porphyrin mol-ecule, two tri-fluoro-methane-sulfonate anions and two water mol-ecules of crystallization. The macrocycle of tetra-pyrrole moieties is planar and unexpectedly it has coordinated Ca ions in occupational disorder. This Ca ion has only 10% occupancy (CHCaFNOS). The pyridinium rings bonded to methyl-ene groups from porphyrin are located in two different arrangements in almost orthogonal positions between the plane formed by the porphyrin and the pyridinium rings. The crystal structure features cation⋯π inter-actions between the Ca atom and the π-system of the phenyl ring of neighboring mol-ecules. Both tri-fluoro-methane-sulfonate anions are found at the periphery of , forming hydrogen bonds with water mol-ecules.