Aragoni M Carla, Arca Massimiliano, Bencini Andrea, Blake Alexander J, Caltagirone Claudia, Danesi Andrea, Devillanova Francesco A, Garau Alessandra, Gelbrich Thomas, Isaia Francesco, Lippolis Vito, Hursthouse Michael B, Valtancoli Barbara, Wilson Claire
Dipartimento di Chimica Inorganica ed Analitica, Università degli Studi di Cagliari, S.S. 554 Bivio per Sestu, 09042 Monserrato (CA), Italy.
Inorg Chem. 2007 Sep 17;46(19):8088-97. doi: 10.1021/ic700657j. Epub 2007 Aug 17.
Two new ligands 7-anthracenylmethyl-13-methylpyridyl-1,4,10-trioxa-7,13-diazacyclopentadecane (L4) and 7-anthracenylmethyl-13-(2,2-dimethyl-2-hydroxyethyl)-1,4,10-trioxa-7,13-diazacyclopentadecane (L(5)) have been synthesized and characterized. Both derive from 7-anthracenylmethyl-1,4,10-trioxa-7,13-diazacyclopentadecane (L(3)) and differ for having a differently functionalized pendant arm covalently attached to the remaining secondary nitrogen donor of the macrocyclic framework. The protonation and coordination behavior of L(4), L(5), and the unbranched L(3) with metal ions have been studied in MeCN/H2O (1:1 v/v, 298.1 K, I = 0.1 M) using potentiometric methods. The crystal structures of L(3), (H2L(3))(HL(3))3, and the complex [CdL(3)(NO3)2] have been determined by single-crystal X-ray methods. The fluorescent behavior of L(3)-L(5) in the presence of Cu(II), Zn(II), Cd(II), Hg(II), and Pb(II) has been studied as a function of pH in MeCN/H2O (1:1 v/v). The presence of Cu(II), Hg(II), or Pb(II) does not affect the fluorescent behavior observed for the three free ligands upon changing the pH. Interestingly, the fluorescent emission of L(3) and L(5) is selectively enhanced only in the presence of Cd(II) at basic pH. The same effect is observed for L4 in the presence of Cd(II) or Zn(II) at about pH 7.
已合成并表征了两种新的配体7-蒽甲基-13-甲基吡啶基-1,4,10-三氧杂-7,13-二氮杂环十五烷（L4）和7-蒽甲基-13-(2,2-二甲基-2-羟乙基)-1,4,10-三氧杂-7,13-二氮杂环十五烷（L5）。两者均衍生自7-蒽甲基-1,4,10-三氧杂-7,13-二氮杂环十五烷（L3），不同之处在于具有一个以共价方式连接到大环骨架其余仲氮供体上的功能化不同的侧链。使用电位滴定法在MeCN/H2O（1:1 v/v，298.1 K，I = 0.1 M）中研究了L4、L5和未分支的L3与金属离子的质子化和配位行为。通过单晶X射线方法测定了L3、(H2L3)(HL3)3和配合物[CdL3(NO3)2]的晶体结构。在MeCN/H2O（1:1 v/v）中，研究了L3 - L5在Cu(II)、Zn(II)、Cd(II)、Hg(II)和Pb(II)存在下的荧光行为随pH的变化。Cu(II)、Hg(II)或Pb(II)的存在不会影响三种游离配体在改变pH时观察到的荧光行为。有趣的是，仅在碱性pH下Cd(II)存在时，L3和L5的荧光发射才会选择性增强。在约pH 7时Cd(II)或Zn(II)存在下，L4也观察到相同的效果。
