Polysulfonyl amines .72. Triphenylcarbenium and triphenylphosphonium di(fluorosulfonyl)amides: Two crystal structures with ordered (FSO2)(2)N-circle minus sites

Treatment of HN(SO2F)(2) in CH2Cl2 with Ph(3)P, Ph(3)PO or collidine (=B) affords the compounds Ph(3)PH(+)[(FSO2)(2)N](-) (3), Ph(3)PO . HN(SO2F)(2), and BH+[(FSO2)(2)N](-) (7). The carbenium salt Ph(3)C(+)[(FSO2)(2)N](-) (5), obtained by metathesisof Ph(3)CBr with [(C6H6)AgN(SO2F)(2)] in CH2Cl2, crystallizes from chloroform/petroleum ether as a monosolvate Ph(3)C(+)[(FSO2)(2)N](-). CHCl3 (6). In presence of a sterically hindered base, viz. collidine, 5 is a suitable reagent for the tritylation of molecules containing weakly activated H atoms (e.g.: MeCN-->Ph(3)CCH(2)CN, acetone-->tritylacetone; co-product: 7). The crystal structures of the ionic solids 3 (monoclinic, space group P2(1)/n) and 6 (monoclinic, P2(1)/c) were determined by X-ray diffraction at -130 degrees C; the structure refinements were not impaired by the notorious tendency of the (FSO2)(2)N moiety towards crystallographic disorder. As in the known structure of the tetraphenylarsonium salt, the anion of 3 and 6 adopts a staggered conformation of approximately C-2 symmetry (averages of all values: S-N-S 121.4 degrees, N-S 156.2, S-O 141.6, S-F 156.6 pm). The crystal packing of 6 displays a three-centre C-H(... O)(2) hydrogen bond between the CHCl3 molecule and two oxygen atoms of a single anion, resulting in a six-membered ring [R(1)(2)(6) pattern; H ... O 234 and 262 pm]. The crystal of 3 contains one-dimensional arrays of alternating cations and anions connected by a three-centre P-H(... O)(2) bond [C-1(2)(6) pattern; H ... O 237 and 254 pm]. The Ph(3)C(+) cation of 6 is propeller-shaped, with three coplanar central bonds (mean C-C 144.5 pm) and interplanar angles of 52.7, 56.4 and 60.1 degrees between the phenyl groups.