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    請使用永久網址來引用或連結此文件: http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/25338

    題名: Tetraorganotellurium(IV) derivatives. Crystal and molecular structure of tetraphenyltellurium-benzene (1/8), (C6H5)4Te.cntdot.1/8C6H6
    作者: 李榮熹;Lee, Jung Si;Smith, Cheryl S.;Titus, Donald D.;Ziolo, Ronald F.
    貢獻者: 淡江大學化學學系
    日期: 1982-02
    上傳時間: 2009-12-01
    出版者: American Chemical Society (ACS)
    摘要: The crystal and molecular structure of tetraphenyltellurium-benzene (1/8) has been determined by a single-crystal X-ray diffraction study. The results represent the first structural Characterization of a tetraorgano derivative of a group 6 element. The compound crystallizes in the space group P1 with eight molecules per unit cell. Lattice parameters (23 f 1 "C) are as follows: a = 14.547 (5) A, b = 21.687 (7) A, c = 13.140 (6) A, a = 101.93 (3)O, 0 = 93.39 (3)O, y = 89.46 (3)", and V = 4052 (2) A3. The structure was determined by Patterson and Fourier methods from automatic diffractometer data using filtered Mo Ka radiation. Refinement by the least-squares technique led to a conventional R factor (on F) of 0.074 for 7893 reflections having F,2 < 3a (F:). Tetraphenyltellurium has a distorted, $-trigonal-bipyramidal geometry with the axial phenyl groups bending toward the equatorial groups. Mean angles are as follows: C,-Te-C = 108.6', C,-Te-C, = 168.7 (7)O, and C,-Te-C, = 86.7 (3)O. The equatorial Te-C distances are norm3 with a mean of 2.13 (0) A. The axial Te-C distances are elongated and range from 2.27 (1) to 2.31 (1) A. These distances are the longest primary Te-C bond distances known. It is suggested that the relative thermal stability of the R,TeX, (n = 2,4) compounds relates, in part, to the stability of the long, axial M6+-.Lb bond. The stereochemistry about Te in the four independent molecules is identical. Each molecule, however, is conformationally unique due to phenyl group orientations. Short intermolecular contacts are absent, giving tellurium a genuine fourfold configuration. The closest Te-Te approach is 4.803 (1) A.
    關聯: Organometallics 1(2), pp.350-354
    DOI: 10.1021/om00062a021
    顯示於類別:[化學學系暨研究所] 期刊論文


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