Affiliation:
1. Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Postfach 3329, 38023 Braunschweig, Germany
Abstract
The four title compounds, Me2NH2
+·(4-Cl/Br/I/Me-C6H4-SO2)2N-, were obtained by metathesis of dimethylammonium chloride with the corresponding silver di(arenesulfonyl)amides. The products crystallize isotypically in the monoclinic space group Cc (Z = 4, Z´ = 1). In each structure, the ionic entities associate into hydrogen-bonded chains, which propagate along the c axis of the crystals and consist of alternating cations and anions held together by charge-assisted N+-H· · ·N− and N+- H(· · ·O)2 hydrogen bonds. In the three structures containing 4-halobenzenesulfonyl groups, each hydrogen-bonded chain is linked to four neighboring chains by pairs of C-Cl/Br/I· · ·O halogen bonds, which at first sight seem to be the causative factor in the formation of catemeric head-to-tail arrays of anions propagating along the ab face diagonals. On suppressing these halogen bonds by means of halogen-methyl exchange, all essential features of the packing architecture, including the anion headto- tail arrays, are precisely maintained. It may be thus inferred that the halogen bonds occurring in the first three compounds are supportive incidentals, but do not play any structure-determining role.