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  • Publication
    Métadonnées seulement
    1,4-Bis(hexyloxy)-2,5-diiodobenzene
    (2010) ; ;
    Sereda, Olha
    ;
    Neels, Antonia
    ;
    The centrosym. title compd., C18H28I2O2, crystd. in the monoclinic space group P21/c with the alkyl chains having extended all-trans conformations, similar to those in the centrosym. bromo analog that crystd. in the triclinic space group P?1. The difference between the 2 structures lies in the orientation of the 2 alkyl chains with respect to the C(arom.)-O bond. In the title compd., the O-Calkyl-Calkyl-Calkyl torsion angle is 55.8(5)°, while in the bromo analog this angle is -179.1(2)°. In the title compd., the C-atoms of the alkyl chain are almost coplanar [max. deviation of 0.052(5) Å] and this mean plane is inclined to the benzene ring by 50.3(3)°. In the bromo-analog, these 2 mean planes are almost coplanar, making a dihedral angle of 4.1(2)°. Another difference between the crystal structures of the 2 compds. is that in the title compd. there are no halide...halide interactions. Instead, symmetry-related mols. are linked via C-H...? contacts, forming a 2D network. Crystal data: monoclinic, P21/n, a = 9.441(9), b = 7.8455(6), c = 13.457(2) Å, ? = 92.148(12)°, Z = 2, 1216 obsd. reflections with I > 2(I), 101 refined parameters, R[F2 > 2?(F2)] = 0.029, wR(F2) = 0.055. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    2-(2-Naphthyl)-1,3-dioxane
    The title compd., C14H14O2, crystallizes in the chiral monoclinic space group P21. Crystallog. data and at. coordinates are given. This acetal is composed of a planar naphthalene ring with a 1,3-dioxane ring substituent, which has a chair conformation. In the crystal structure, symmetry-related mols. are connected via a weak C-H...O interaction to form a helical chain propagating in [010]. While there are no ?-? stacking interactions present, there are weak C-H...? interactions involving the naphthalene arom. rings, which link the helical chains to form a two-dimensional network in the (011) plane. [on SciFinder(R)]
  • Publication
    Métadonnées seulement
    1,4-Bis[4-(tert-butyldiphenylsilyl)buta-1,3-diynyl]benzene
    The title centrosym. mol., C46H42Si2, is composed of a central benzene ring with buta-1,3-diynyl chains at positions 1 and 4. These chains are terminated by tert-butyldiphenylsilyl groups, hence the mol. is dumbbell in shape. The mols. are connected via C-H...? interactions in the structure, so forming an undulating 2D network in the bc plane. There is also a weak ?-? interaction involving centrosym. related Ph rings with a centroid-centroid distance of 3.8359(11) Å. Crystal data: monoclinic, P21/c, a = 8.535(1), b = 17.2060(14), c = 13.4923(14) Å, ? = 104.064(9)°, Z = 2, 3260 obsd. reflections with I > 2(I), 220 refined parameters, R[F2 > 2?(F2)] = 0.044, wR(F2) = 0.104. [on SciFinder(R)]