Synthesis and Crystal Structures of Two New Oxaspirocyclic Compounds

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) angstrom , b = 14.605(3) angstrom , c = 16.265(3) angstrom, beta = 95.97(3)degrees, V = 1477.9(5)angstrom(3) , Z = 4, D-c = 1.354 g/cm(3), F(000) = 640, mu (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), b = 18.348(4), c = 6.7799(14) , beta = 104.20(3)degrees, V = 1295.1(5)angstrom(3), Z = 4, D-c = 1.407 g/cm(3), F(000) = 608, mu(MoKa) = 0.106mm(-1), the final R = 0.0568 and wR = 0.1739. Some C-H O intra-and intermolecular hydrogen bonds and pi center dot center dot center dot pi stacking interactions are both observed in the two lattice structures. The difference between them is that one type of C-H center dot center dot center dot pi supramolecular interaction (1) and one type of O-H O intermolecular hydrogen bond (2) are observed.