A new hydrated benzimidazolium salt containing spiro structure was obtained when benzimidazole is added to ethyl alcohol of 1,5-dioxaspiro[5.5]undecane-2,4-dione and trimethoxymethane. The title compound (C₁₉H₂₁O₈) (C₇H₇N₂) (0.5H₂O) was characterized by elemental analysis, IR, UV-Vis, and single-crystal X-ray diffraction. The result shows that it belongs to the triclinic system, space group P-1, with a = 11.017(2) Å, b = 11.424(2) Å, c = 11.650(2) Å, α = 70.60(3)°, β = 71.00(3)°, γ = 67.64(3)°, Mr = 505.51, V = 1245.2(5) Å, Z = 2, Dc = 1.348 g/cm³, F(000) = 534, μ(MoKa) = 0.102 mm⁻¹. There exist two types of hydrogen bonds in the crystal. (C₁₉H₂₁O₈)⁻ anions and (C₇H₇N₂)⁺ cations are linked by N–H···O hydrogen bonds, while (C₁₉H₂₁O₈)⁻ anions and free water are linked by O–H···O hydrogen bonds. All of the above hydrogen bonds form a one-dimensional (1D)-chained structure. The 1D chains further links the molecule into a three-dimensional (3D)-layered structure.

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) ų, 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) ų, 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.

A new trinuclear Cd (II) complex [Cd₃(L)₆(2,2-bipyridine)₃] [L = N-phenylsulfonyl-L-leucinato] has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction analysis. The results show that the complex belongs to the orthorhombic, space group P2₁2₁2₁ with a = 16.877(3) Å, b = 22.875(5) Å, c = 29.495(6) Å, α = β = γ = 90°, V = 11387(4) ų, Z = 4, D_c= 1.416 μg·m⁻³, μ = 0.737 mm⁻¹, F (000) = 4992, and final R₁ = 0.0390, ωR₂ = 0.0989. The complex comprises two seven-coordinated Cd (II) atoms, with a N₂O₅ distorted pengonal bipyramidal coordination environment and a six-coordinated Cd (II) atom, with a N₂O₄ distorted octahedral coordination environment. The molecules form one dimensional chain structure by the interaction of bridged carboxylato groups, hydrogen bonds and p-p interaction of 2,2-bipyridine. The luminescent properties of the Cd (II) complex and N-Benzenesulphonyl-L-leucine in solid and in CH₃OH solution also have been investigated.

Two new oxaspirocyclic compounds, 8-(4-(dimethylamino)benzylidene)-6,10-dioxaspiro[4.5]decane-7,9-dione (1) and 8-(4-hydroxybenzylidene)-6,10-dioxaspiro[4.5]decane-7,9-dione (2) have been synthesized and their structures determined by single crystal X-ray crystallography. Compound 1, C₁₇H₁₉NO₄, belongs to the monoclinic system, space group P21/c with a = 6.2554(13) Å, b = 14.605(3) Å, c = 16.265(3) Å, β = 95.97(3)°, V = 1477.9(5) ų, Z = 4, D_c = 1.354 g/cm³, F(000) = 640, μ(MoKa) = 0.097 mm⁻¹, the final R = 0.0570 and wR = 0.1667. Compound 2, C₁₅H₁₄O₅, is also of the monoclinic system, space group P21/c with a = 10.739(2) Å, b = 18.348(4) Å, c = 6.7799(14) Å, β = 104.20(3)°, V = 1295.1(5) ų, Z = 4, D_c = 1.407 g/cm³, F(000) = 608, μ(MoKa) = 0.106 mm⁻¹, the final R = 0.0568 and wR = 0.1739. Some C–H···O intra- and intermolecular hydrogen bonds and π··· π stacking interactions are both observed in the two lattice structures. The difference between them is that one type of C–H···π supramolecular interaction (1) and one type of O–H···O intermolecular hydrogen bond (2) are observed.

Two new compounds, 8-(3,4,5-trimethoxybenzylidene)-6,10-dioxaspiro[4,5]decane-7,9-dione (J1) and 8-(3,4,5-trimethoxybenzyl)-6,10-dioxaspiro[4,5]decane-7,9-dione (J2) have been designed and generated by the reaction of 3,4,5-trimethoxybenzaldehyde with 6,10-dioxaspiro[4,5]decane-7,9-dione in different solvents. The 3,4,5-trimethoxybenzyl group of the two compounds connects with the dioxaspiro group via double bond (J1) and single bond (J2), respectively. The crystal structure determinations show that Compound J1 belongs to the triclinic system, space group P-1 with a = 5.4056(11) Å, b = 11.465(2) Å, c = 13.502(3) Å, α = 92.06(3)° Å, β = 91.35(3)°, γ = 93.50(3)°, C₁₈H₂₀O₇, Mr = 348.34, V = 834.4(3) ų, Z = 2, Dc = 1.386 g/cm³, F(000) = 368. Compound J2 is also of the triclinic system, space group P-1 with a = 8.8778(18) Å, b = 9.5285(19) Å, c = 11.082(4) Å, α = 89.69(3)°, β = 67.38(3)°, γ = 81.68(3)°, C₁₈H₂₂O₇, Mr = 250.36, V = 854.9(3) ų, Z = 2, Dc = 1.361 g/cm³, F(000) = 372. Both compounds form three-dimensional network structures via C–H···O intra- and intermolecular hydrogen bonds.

A precursor, C₂₁H₂₉NO₈ (A1) was prepared by reactions of 1,1-dimethoxy-N,N-dimethylmethanamine and 1,5-dioxaspiro[5.5]undecane-2,4-dione. The new N-containing heterocyclic compound, C₁₉H₁₉NO₄ (B1) was obtained by adding A1 into ethanol solution of o-toluidine. The crystal structure determination of two compounds were both found to belong to the triclinic P-1 space group. The precursor includes one (C₂H₈N)⁺ cation and one (C₁₉H₂₁O₈)⁻ anion, which constituted a chained structure by N–H···O intra- and intermolecular interactions. The title compound (B1) formed a 3D-network structure by weak C–H···O intermolecular interactions and π···π stacking interactions. The fluorescent behaviors of A1 and B1 in ethanol solution were discussed. The result shows that they exhibit blue and purplish blue emission, respectively.