Halogen bonded networks from pyridyl-substituted tetraarylethylenes and diiodotetrafluorobenzenes

Abstract

Three halogen bonded co-crystals between tetraphenylethylene derivatives with peripheral pyridine groups and 1,4- or 1,2-diiodotetrafluorobenzene have been characterized. Two crystalline networks prepared from 3-pyridyl-substituted tetraphenylethylene exhibit remarkably similar topologies, each featuring an open square grid lattice assembled from the tetraphenylethylene component that surrounds π-stacked 1,2- or 1,4-diiodoarene halogen bond donors. The ratio of tetraphenylethylene to diiodoarene is 1 : 2 in each case, and all pyridine and iodoarene groups are engaged in halogen bonding interactions. Co-crystals obtained from 4-pyridyl-substituted tetraphenylethylene and 1,4-diiodotetrafluorobenzene, however, exhibit a 1 : 1 ratio of components with only a single pyridine N⋯I halogen bond.