A Slow Leak Synthetic Route to Organically Templated Gallium Sulfates

Single crystals of the first four organically templated gallium sulfates were prepared under mild hydrothermal conditions: [C2H10N2][H3O][Ga(SO4)3], [C2H10N2][Ga(OH)(SO4)2]·H2O, [C6H18N2][Ga(H2O)2(SO4)2]2, and [C4H14N2][Ga(H2O)2(SO4)2]2. These compounds contain either [Ga(SO4)3]n3n−, [Ga(OH)(SO4)2]n2n−, or [Ga(H2O)2(SO4)2]nn− chains or [Ga(H2O)2(SO4)2]nn− layers, respectively, and protonated organic amine dications. Reactions were conducted in 15 mL polypropylene bottles at 100 °C. A slow leak solvent evaporation technique allowed for the use of sparingly soluble oxide starting materials, gently increased reactant concentrations, and facilitated the growth of high quality single crystals over 1.5 d. Differences in composition and structure between [C2H10N2][H3O][Ga(SO4)3], [C2H10N2][Ga(OH)(SO4)2]·H2O, [C4H14N2][Ga(H2O)2(SO4)2]2, and [C6H18N2][Ga(H2O)2(SO4)2]2 reflect the initial reagent concentrations and amine structures.