Crystal Structures of a New Polymorph of N-tert-butyl-2-thioimidazole, and Its 1,4-Diiodotetrafluorobenzene, Tetraiodoethylene, and Iodine Cocrystals

A new polymorph of N-tert-butyl-2-thioimidazole (1), along with its cocrystals with 1,4-diiodotetrafluorobenzene (2), tetraiodoethylene (3), and molecular iodine (4) have been synthesized. Compound 1 is a new polymorph of a previously reported structure. A series of noncovalent N–H⋯S, N–H⋯I, and I⋯S interactions all contribute to the packing. In 1–3, a pair of N–H⋯S contributes to the formation of imidazole dimers, a commonly observed motif for these systems, which are then linked together through C–I⋯S halogen bonding. This halogen bond occurs approximately normal to the imidazole ring plane. In 4, the addition of I2 to the sulfur atom interrupts N–H⋯S dimer formation, with the primary interactions between neighboring imidazole molecules being of the N–H⋯I and C=S⋯I. This variety of intermolecular interactions leads to the formation of double-stranded chains, ribbons, and sheets. A new polymorph of N-tert-butyl-2-thioimidazole, along with its cocrystals with 1,4-diiodotetrafluorobenzene, tetraiodoethylene, and molecular iodine have been synthesized. A series of noncovalent N–H⋯S, N–H⋯I, and I⋯S all contribute to the packing