POLYSULFONYL AMINES .40. PREPARATION OF SILVER(I) DISULFONYLAMIDE ACETONITRILE COMPLEXES - CHARACTERIZATION OF TETRAACETONITRILESILVER(I) BIS(DIMESYLAMIDO)ARGENTATE(I) AND (1,1,3,3-TETRAOXO-1,3,2-BENZODITHIAZOLIDO)ACETONITRILESILVER(I) BY X-RAY-DIFFRACTOMETRY AND THERMAL-ANALYSIS

The following silver(I) disulfonylamides were prepared for the first time or by improved procedures: AgN(SO2CH3)2 (2a); AgN(SO2C6H4-4-X)2 with X = F (2b), Cl (2c), Br (2d), CH3 (2e); silver(I) 1,2-benzenedisulfonimide AgN(SO2)2C6H4 (2f). With acetonitrile, the salts 2a to 2e form (1/2) complexes AgN(SO2R)2 . 2CH3CN (4a to 4e), whereas 2f gives the (1/1) complex AgN(SO2)2C6H4 . CH3CN (4f). The crystallographic data (at -95-degrees-C) for the title compounds 4a and 4f are: 4a, space group C2/c, a = 1967.6(4), b = 562.2(1), c = 2353.0(5) pm, beta = 102.21(2)degrees, V = 2.5440 nm3, Z = 4, D(x) = 1.891 Mg m-3; 4f, space group P2(1)/m, a = 741.5(3), b = 980.4(4), c = 756.6(3) pm, beta = 99.28(2)degrees, V = 0.5428 nm3, Z = 2, D(x) = 2.246 Mg m-3. 4a forms an ionic crystal [Ag(NCCH3)4]+[Ag{N(SO2CH3)2}2]- with a tetrahedrally coordinated silver atom (lying on a twofold axis) in the cation (225.3/225.7 pm for the two independent Ag-N distances, N-Ag-N 106.2-114.5-degrees) and a linear-dicoordinated silver atom in the centrosymmetric anion (Ag-N 213.9 pm, two intra-ionic secondary Ag ... O contacts 303.4 pm). 4f consists of uncharged molecules [C6H4(SO2)2N1AgN2CCH3] with crystallographic mirror symmetry (Ag-N1 218.8, Ag-N2 216.1 pm, N1-Ag-N2 174.3-degrees), associated into strands by intermolecular secondary silver-oxygen contacts (Ag ... O 273.8 pm, O ... Ag ... O 175.6, N-Ag ... O 91.9/88.2-degrees). The thermochemical behaviour of 4f was investigated using thermogravimetry, differential scanning calorimetry (DSC), time- and temperature-resolved X-ray diffractometry (TXRD), and solution calorimetry. The desolvation process occurs in the temperature range from 60 to 200-degrees-C and appears to be complex, although no crystalline intermediate could be detected. The desolvation enthalpy at 298 K was found to be +26.8(4) kJ mol-1. 4 a is desolvated in two steps at -15 to 60-degrees-C and 60 to 95-degrees-C (DSC), suggesting the formation of AgN(SO2CH3)2 . CH3CN as an intermediate.