Three isomers of I have the same melting point, 133°, and diagnostically different, but not interpretable, infrared spectra.Stability constants for formation of complexes with potassium bromide in methanol are 1.5 x ~0 8 , 3.2 x 10 6 and 4.5 x 10 4 1 mol-1 . The third isomer also yields from methanol crystals of a 1:1 solvate with an infrared spectrum indicating no hydrogen bonding by the OH group.The configuration of each of the three isomers has been determined by X-ray diffraction.Intensities were measured on a CAD4 diffractometer with Mo-Ka radiation; the phase problem 1ms solved by direct methods and final parameters obtained by full matrix refinement.Hydrogen atoms were located unequivocally.There is a cis substitution at the cyclohexane bridges, at each of---which the hydrogen atoms may be on the same or the opposite side as the OCH 2 CH 2 oc 6 H 4 0CH 2 CH 2 0 link. The configurations provide a basis for understanding their behaviour as ligands.Ia Monoclinic,~= 15.613 (2), ~ = 21.492(4), £ = 8.021(1) A, S = 96.99°, l = 4 in P2 1 /a. R = 0.078 for 2163 reflections. Ib Tric1inic, ~ = 8.842(2), ~ = 16. 702(6), £ = 10.050(3), a= 114.10(3), S = 98.97(2), £ = 91.22(2) 0 , Z = 2 in Pl. 2666 observed reflections. R = 0.060 for Ic, CH 3 0H Monoclinic,~= 14.520(2), £_ = 15.391(3), £ = 12.754(2), S = 95.02(2) 0 , l = 4 in P2 1 /n. R = 0.062 for 2071 observed reflections. The shortest (hydroxy) H ... 0 (ligand) distances are 2.37 and 2.31(10) .ill. Crystal structures of complexes Hi th alkali metal salts are being investigated.
Abstract. CivH2008, monoclinic, P2i/b, Z = 4, a = 10.798(11), b = 9.057(10), c = 17.585 (31)A, y = 93.02 (2) ° , V= 1717.4/~3 Dx = 1.36 Mg m -3,/~= 0.106 mm -l. The structure was solved by direct methods and refined by least-squares procedures to a final R of 0.048 for 2254 independent reflections. The interatomic distances and bond angles are in good agreement with previously published values. The 15-membered ring forms a distorted square. The three ester groups are in the trans form: two groups are almost perpendicular to the mean plane of the macrocycle and the third is displaced from it. The overall conformation is stabilized by both intra-and
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