Crystal structures of four inclusion compounds of 2,2′-dithiosalicylic acid and tetraalkylammonium

Abstract

ABSTRACTHerein four inclusion compounds of 2,2′-dithiosalicylic acid and tetraalkylammonium, 2(CH3)4N+·C14H8O4S22−·H2O (1), (C2H5)4N+·C14H9O4S2−·0.25H2O(2), (n-C3H7)4N+·C14H9O4S2− (3) and (n-C4H9)4N+·C14H9O4S2−(4) are prepared and characterized by X-ray single crystal diffraction. As shown in the results, compounds 1 and 3 belong to orthorhombic crystal system with different space groups of P212121 and Pca21, and 2 and 4 are monoclinic system with similar groups of P21/n and P21/c. The crystallography data are displayed below: 1: a = 10.5903(7) Å, b = 10.6651(7) Å, c = 21.9476(13) Å, V = 2478.9(3) Å3, Z = 4, R1 = 0.0359; 2: a = 8.13340(1) Å, b = 22.0741(3)Å, c = 13.2143(2)Å, β = 101.6360(1) °, V = 2323.70(6) Å3, Z = 1, R1 = 0.0385; 3: a = 15.7857(2) Å, b = 8.24830(1) Å, c = 20.2599(2) Å, V = 2637.94(5) Å3, Z = 4, R1 = 0.0308degree4: a = 11.7476(2) Å, b = 17.1346(1) Å, c = 16.3583(3)Å, β = 109.4560(1) °, V = 3104.74(9)Å3, Z = 4, R1 = 0.0562. Interestingly, although the carbon chains of the guest templates vary from methyl group to butyl group, the host molecules of 2,2′-dithiosalicylic acid all construct the similar 2D hydrogen-bonded host layers with or without the existence of water molecules to contain the guest templates to yield analogous sandwich-like inclusion compounds. Obviously, although the guest templates will have certain effects on the ultimate formation of these crystal structures, the host molecule of 2,2′-dithiosalicylic acid is a controlling factor to form these four inclusion compounds.