synthesis of norbornadienobenzene fused crown ethers

• Main Authors: Yi-Pin Lin, 林憶苹
• Other Authors: Teh-Chang Chou
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/71705259435553958757

碩士 === 國立中正大學 === 化學研究所 === 90 === A series of crown ethers, 61、62、63、64, were synthesized from 2,3-dicyanohydroquinone (79) in seven key steps. The association constants for 1︰1 complexs of crown ethers with several cations (Li+, Na+, K+, Cs+, NH4+) have been determined by means of UV-visible spectroscopy、electrospray ionization-mass spectrometry and X-ray diffraction. The absorption spectra of complexs show, in addition to maxima that are slightly red-shifted in comparison with the original crown ethers, an absorption at 360∼370 nm due to picrate anion. Moreover, the interaction between crown ethers and cation size is manifested by the selectivity order, wihich changes from Na+＞K+＞Li+＞NH4+＞Cs+ for 61, Na+，K+＞Li+＞NH4+＞Cs+ for 62, Na+，K+＞NH4+＞Li+＞Cs+ for 63, to K+＞Na+＞NH4+＞Cs+＞Li+ for 64, in line with the results of ESI—MS study. The X-ray crystal structure shows the complex of crown ether 62 with potassium can form 2︰1 (crown︰K+) complex with〝sandwich〞structure.