Multiple bismuth(III)-thioether secondary interactions integrate metalloporphyrin ligands into functional networks

We introduce the 1,2,3-tris(organylthiophenyl) group as a symmetrical, multidentate chelation link for building coordination networks. For this, zinc(II) 5,10,15,20-tetrakis[3′,4′,5′-tris(methylthio)phenyl] porphyrin was synthesized and integrated into a two-dimensional network via coordination with BiBr₃. The coordination link exhibits an unusually complex bonding pattern, involving six S atoms from two neighboring ligands that form multiple Bi-S interactions (distances ranging from 3.08 to 3.63 Å) with a dimerlike unit of Bi₂Br₆. The electronic interaction between the porphyrin center and the Bi₂Br₆ block was illustrated by the diffuse-reflectance spectrum of the network compound, in which a modest red-shifted feature at 1.8 eV was seen (while the Q-band absorption of the metalloporphyrin core continues to be dominant at 1.9 eV).