English  |  正體中文  |  简体中文  |  Items with full text/Total items : 69937/69937 (100%)
Visitors : 23134561      Online Users : 470
RC Version 7.0 © 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://ir.lib.ncu.edu.tw/handle/987654321/50947

    Title: Synthesis of quinoxaline-benzoxale conjugates and mesomorphic properties
    Authors: Chen,CJ;Wu,YC;Sheu,HS;Lee,GH;Lai,CK
    Contributors: 化學學系
    Date: 2011
    Issue Date: 2012-03-27 18:13:28 (UTC+8)
    Publisher: 國立中央大學
    Abstract: A new series of non-discotic heterocyclic compounds 1a-e derived from quinoxaline was prepared and their mesomorphic properties investigated. The crystal and molecular structures of nonmesogenic 2,3-bis(3,4-didodecyloxyphenyl)quinoxaline-6-carboxylic acid 4-[(4-butoxy2-hydroxyphenylimino)methyl] phenyl ester 2a (n=4, m=12) were determined by means of X-ray structural analysis. It crystallizes in a monoclinic space group P2(1)/c, with a=21.9193(13) angstrom, b=8.3693(4) angstrom, c=30.896(2) angstrom, and Z=4. The molecule was considered as an elongated or tapered triangle. Both inter- and intra-molecular H-bonds were observed in the crystal lattice, which was attributed to the formation of columnar mesophase in compounds 2. The mesomorphic behavior of compounds 1-2 was studied by thermal analysis and polarized optical microscopy. All compounds 1-2 exhibited hexagonal columnar phases (Col(h)), which were also confirmed by powder XRD diffractometer. A N(cell) and R(ar) value equal to 4.74 and 4.34 within a slice of 9.0 angstrom thick were obtained for 1b and 2b, indicating that a more disc-like correlated structure by two molecules lying side-by-side was formed in Col(h) phases. The fluorescent properties of the compounds 1-4 in CH(3)Cl were also examined. (C) 2010 Elsevier Ltd. All rights reserved.
    Relation: TETRAHEDRON
    Appears in Collections:[化學學系] 期刊論文

    Files in This Item:

    File Description SizeFormat

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

    社群 sharing

    ::: Copyright National Central University. | 國立中央大學圖書館版權所有 | 收藏本站 | 設為首頁 | 最佳瀏覽畫面: 1024*768 | 建站日期:8-24-2009 :::
    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback  - 隱私權政策聲明