Study of energy transfer in a naphthalene-linked crown ether–Eu3+ complex: the effect of the orientation of the naphthalene π-plane with respect to the Eu3+ ion
摘要:
The energy transfer (ET) from naphthalene (N) to EU3+ has been studied in complexes of the Eu3+ ion with 2,3-naphtho-17-crown-5, 2,3-naphtho-20-crown-6, 1,8-naphtho-21-crown-6 and 1,5-naphtho-22-crown-6, respectively, using the NO ion as the counter anion in EtOH glass at 77 K. Both the ET efficiency and the N-phosphorescence quenching show a strong dependence on the orientation of the N-pi-plane with respect to the Eu3+ ion. The results suggest that an exchange mechanism involving the lowest excited triplet state of N and D-5(2) states of the rare-earth ions is mainly operating. (C) 1998 Elsevier Science B.V. All rights reserved.
Synthesis of crown ethers that geometrically orient cations relative to a naphthalene .pi. system. A look at the equilibration of enantiomeric conformations by "rope-skipping" crown ethers
The dependence of photoinduced energy transfer on the orientation of the acceptor with respect to the π-plane of the donor in naphthalene-linked crown ether–Tb3+ complexes
predetermined orientation with respect to the naphthalene molecular plane. In systems I and II, the Tb3+ ion is along the Z-axis; in system III, it is along the Y-axis and in IV, it is along the X-axis, where Z- and Y- are the molecular in-plane long and short axes of the naphthalene molecular plane respectively and X- is the out-of plane axis perpendicular to the naphthalene molecular plane. Present studies indicate
研究了Tb 3+离子与2,3-naphtho-17-crown-5醚(I),2,3-naphtho-的络合物中从萘(N)到Tb 3+的光致能量转移(ET)。20冠-6-醚(II),1,8-二萘并-21-冠-6醚(III)和1,5-萘并-22-冠-6醚(IV),分别使用硝酸盐(NO 3 -离子在77 K EtOH玻璃中作为抗衡阴离子。如此设计配体,使得Tb 3+离子可以相对于萘分子平面以预定的取向络合。在系统I和II中,Tb 3+离子沿Z轴;在系统III中,它沿着Y轴,在系统IV中,它沿着X轴,其中Z-和Y-分别是萘分子平面的分子内平面长轴和短轴,而X-是垂直于萘分子平面的面外轴。目前的研究表明,能量转移(ET)的效率和萘磷光的猝灭显示出强烈依赖于受体金属离子(Tb 3+)相对于供体萘部分的π平面的方向。ET研究表明,一种交换机制涉及N的最低(ππ *)三重态和Tb 3+的5 D 4态。离子
Synthesis of crown ethers that geometrically orient cations relative to a naphthalene .pi. system. A look at the equilibration of enantiomeric conformations by "rope-skipping" crown ethers
作者:Houston S. Brown、Chrysa P. Muenchausen、Lynn R. Sousa
DOI:10.1021/jo01297a031
日期:1980.4
Study of energy transfer in a naphthalene-linked crown ether–Eu3+ complex: the effect of the orientation of the naphthalene π-plane with respect to the Eu3+ ion
作者:Surajit Bhattacharyya、L.R. Sousa、Sanjib Ghosh
DOI:10.1016/s0009-2614(98)01078-1
日期:1998.11
The energy transfer (ET) from naphthalene (N) to EU3+ has been studied in complexes of the Eu3+ ion with 2,3-naphtho-17-crown-5, 2,3-naphtho-20-crown-6, 1,8-naphtho-21-crown-6 and 1,5-naphtho-22-crown-6, respectively, using the NO ion as the counter anion in EtOH glass at 77 K. Both the ET efficiency and the N-phosphorescence quenching show a strong dependence on the orientation of the N-pi-plane with respect to the Eu3+ ion. The results suggest that an exchange mechanism involving the lowest excited triplet state of N and D-5(2) states of the rare-earth ions is mainly operating. (C) 1998 Elsevier Science B.V. All rights reserved.