INCLUSION-COMPOUNDS OF THIOUREA AND PERALKYLATED AMMONIUM-SALTS .2. HYDROGEN-BONDED HOST LATTICES BUILT OF THIOUREA AND CYCLIC DIMERIC BICARBONATE MOIETIES

New inclusion complexes R(4)N(+)HCO(3)(-).x(NH2)(2)CS.yH(2)O (1, R = C2H5, x = 1, y = 1; 2, R = n-C3H7, x = 2, y = 0; 3, R = n-C4H9, z = 3, y = 0) have been prepared and characterized by X-ray crystallography. Crystal data, MoKalpha, radiation: 1, space group Pbca, Z = 8, a = 8.839(2), b = 14.930(3), c = 24.852(5) Angstrom, and R(F) = 0.063 for 1419 observed data; 2, space group C222(1), Z = 8, a = 8.521(3), b = 16.941(4), c = 32.022(7) Angstrom, R(F) = 0.054 for 1689 observed data; 3, space group P (1) over bar, Z = 2, a = 9.553(2), b = 12.313(3), c = 14.228(4) Angstrom, alpha = 90.44(2), beta = 103.11(2), gamma = 110.12(2)degrees, R(F) = 0.044 for 3925 observed data. In the crystal structure of 1, the thiourea molecules form hydrogen-bonded zigzag ribbons running parallel to the a axis, and the cyclic dimeric bicarbonate moieties (HCO3-)(2) together with water molecules behave likewise. A puckered layer: is formed by further lateral hydrogen bonding between these two types of ribbons, and the (C2H5N+ cations occupy the space between adjacent layers. In the crystal structure of 2, the thiourea ribbons are cross-linked orthogonally by (HCO3-)(2) units via N-H...O hydrogen bonds to form a composite double layer. Half of the cations are enclosed within and the other half sandwiched between these double layers. In the crystal structure of 3, the thiourea molecules form puckered double ribbons running in the [110] direction. The host framework is constructed by cross-linking the double ribbons with bridging bicarbonate dimers, yielding two channel systems aligned parallel to [100] and [111] that accommodate the cationic guests. The structural relationship between the present complexes and the classical thiourea channel adducts is discussed.