The role of functional nitro and cyano groups in the self-assembly of 1,3-dithiole-2-thione–halogen adducts

The synthesis of five new dihalogen/interhalogen charge transfer adducts featuring cyano and nitro functionalized 1,3-dithiole-2-thiones have been prepared and characterized by x-ray crystallography. The structures feature a complex series of intermolecular close contacts between heteroatoms, as well as hydrogen bonding, to give highly ordered, polymeric assemblies. The adduct 4.IBr crystallizes in a noncentrosymmetric chiral space group and features a stack of molecules assembled through hydrogen bonds. The functional groups of all adducts participate in networks of close contacts, but do not affect the coordination environment of the dihalogen/interhalogen species. (c) 2007 Wiley Periodicals, Inc.