Self-assembly of halogen adducts of ester and carboxylic acid functionalised 1,3-dithiole-2-thiones

New halogen adducts of 1,3-dithiole-2-thione-4-carboxylic acid and dimethyl 1,3-dithiole-2-thione-4,5-dicarboxylate have been prepared and characterised by X-ray crystallographic studies. The adducts feature an array of intramolecular and intermolecular close contacts involving chalcogen-chalcogen, chalcogen-halogen and halogen-halogen interactions. Whilst these contacts are derived from the basic heterocyclic unit and the coordinated halogen molecules, the ester and acid functionalities provide a varied and rich array of hydrogen bonding motifs, which significantly enhance the long-range order of the supramolecular structures.