English  |  正體中文  |  简体中文  |  Items with full text/Total items : 90074/105197 (86%)
Visitors : 7156369      Online Users : 37
RC Version 6.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version

    Please use this identifier to cite or link to this item: http://asiair.asia.edu.tw/ir/handle/310904400/17353

    Title: Conformational Analysis of trans- 2,11-Dithia-4e,5,6,7e,8,9-hexahydro[3.3]paracyclophane Using VT-NMR
    Authors: Ya-Chen Yang;Chen-Huei Lin;Lee-Huei Lin;Shaw-Tao Lin
    Contributors: 保健營養生技學系
    Keywords: Hexahydrocyclophane;VT-NMR;Coalescence temperature;MM2;Ring-inversion.
    Date: 2012-04
    Issue Date: 2012-11-26 10:31:53 (UTC+8)
    Abstract: The conformation of trans-2,11-dithia-4e,5,6,7e,8,9-hexahydro[3.3]paracyclophanes (5, tDTHHPCP) was investigated by using H-1 NMR analysis under variable-temperature condition. Based on the dynamic H-1 NMR behavior along with a structure obtained from simulation using the MM2 method, it has been deduced that 5 occurs preferentially in conformer 5a in CD2Cl2 solution, which the two sulfur atoms are situated as the chair form and cyclohexano unit as a distorted boat form. The energy barrier (Delta G double dagger) for the inversion of the bridge (-CH2SCH2-) has been estimated to be 11.6 kcal mol(-1) (600 MHz, Tc = -30 degrees C). The proton chemical shifts are assigned for the individual hydrogen according to the spectra obtained at -70 degrees C.
    Appears in Collections:[食品營養與保健生技學系] 期刊論文

    Files in This Item:

    File Description SizeFormat

    All items in ASIAIR are protected by copyright, with all rights reserved.

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback