The reactions of imidazoquinoxaline and 1,3,5-H3 btc acid under different condition have been investigated. The different degree of hydrolysis reaction leads to two different adducts being produced, namely, [(Hdiam Quin)+(H2btc)-](1), and [(diam Quin)4(Imi Quin)·4H2O](2). Both compounds were characterized by X-ray crystallography. Crystal data for 1: monoclinic, space group Pn with a = 9.868(2), b = 5.3172(11), c = 15.387(3) ?, β = 91.10(3)o, C17H14N4O6, Mr = 370.32, V = 807.2(3) ?3, Z = 2, Dc = 1.524 g/cm^3, μ(Mo Kα) = 0.118 mm-1, F(000) = 384, the final R = 0.0385 and w R = 0.0869 for 2294 observed reflections(I > 2σ(I)). Crystal data for 2: triclinic, space group P1 with a = 9.825(2), b = 14.144(3), c = 16.054(3) ?, α = 101.06(3), β = 102.55(3), γ = 92.46(3)o, C_(44)H40N_(20)O_4, Mr = 912.96, V = 2128.8(7) ?3, Z = 2, Dc = 1.424 g/cm^3, μ(Mo Kα) = 0.099 mm-1, F(000) = 952, the final R = 0.0554 and w R = 0.1662 for 6563 observed reflections(I > 2σ(I)). X-ray diffraction analysis reveals that compound 1 is a salt. Imidazoquinoxaline was wholly hydrolyzed into 2,3-diaminoquinoxaline and protonated as a cation with H2btc-acting as an anion. However, in compound 2, the imidazoquinoxaline is only partly hydrolyzed, and the resulting 2,3-diaminoquinoxaline forms adduct with the intacted imidazoquinoxaline. Both are further aggregated into 3D frameworks by strong hydrogen bonding even π-π interactions.
