Synthesis and Crystal Structures of Two Novel O, N-Containing Spiro Compounds

Two novel O, N-containing spiro compounds, C16H16ClNO4 (1) and C16H16N2O6 (2), were prepared by reactions of monosubstituted benzenamine (substituent = –NO2, –Cl) and 1,5-dioxaspiro[5.5]undecane-2,4-dione in ethanol solution of trimethoxymethane. Their structures were characterized by elemental analysis, IR, UV-Vis and single-crystal X-ray diffraction. Compound 1 is triclinic with space group P-1 and cell constants: a = 5.9448(12), b = 9.782(2), c = 13.480(3) Å, α = 100.28(3)°, β = 100.66(3)°, γ = 97.83(3)°, Mr = 321.75, V = 746.3(3) Å3, Z = 2, Dc = 1.432 g/cm3, F(000) = 336, μ(MoKa) = 0.274 mm−1, the final R = 0.0544 and wR = 0.1538. Compound 2 is monoclinic with space group P21/c and cell constants: a = 12.472(3), b = 11.856(2), c = 10.643(2) Å, β = 99.83(3)°, Mr = 332.31, V = 1550.7(5) Å3, Z = 4, Dc = 1.423 g/cm3, F(000) = 696, μ(MoKa) = 0.110 mm−1, the final R = 0.0444 and wR = 0.1187. In 1, there exist some intra- and inter-molecular hydrogen bonds and C–H···π supramolecular interactions, while there are still π···π stacking interactions except for some intra- and intermolecular hydrogen bonds in 2. Two compounds both form a three-dimensional network structure via above intermolecular interactions