Proton-controlled photoisomerization: rhenium(i) tricarbonyl bipyridine linked to amine or azacrown ether groups by a styryl pyridine bridging ligand
作者:Jared D. Lewis、Robin N. Perutz、John N. Moore
DOI:10.1039/b005889k
日期:——
Complexes in which fac-(bpy)Re(CO)3 is linked by a styrylpyridine to an amine or an azacrown ether show no photoreaction in acetonitrile in the absence of acid, but they photoisomerize readily at the stilbene-like bridging ligand when the terminal amine or azacrown ether group is protonated because an intramolecular energy-transfer mechanism becomes available.
Cation sensors containing a (bpy)Re(CO)3 group linked to an azacrown ether via an alkenyl or alkynyl spacer: synthesis, characterisation, and complexation with metal cations in solution
作者:Jared D. Lewis、John N. Moore
DOI:10.1039/b401092b
日期:——
alkali-metal (Li+, Na+ and K+) or alkaline-earth metal (Mg2+, Ca2+ and Ba2+) cations to the azacrown; the magnitude of the blue shift is dependent on the cation, with protonation giving the largest shift of ca. 100 nm. Cationbinding constants in the range of log K = 1–4 depend strongly on the identity of the metal cation. Protonation or cation complexation causes downfield shifts in the 1H NMR resonances from
两个[(bpy)Re(CO)3 L] +络合物(py = 2,2'-联吡啶),其中L含有连接到重新氮杂-15-冠-5醚经由一个烯基-或炔基-吡啶间隔基已与模型配合物一起合成。复杂的解决方案乙腈 已经通过UV-Vis吸收进行了研究 光谱学,然后按一维和 2D 1 H NMR 光谱学。强的紫外可见 分配给L内配体内电荷转移跃迁的谱带 配体,蓝色转变为氮杂皇冠的质子化 氮原子或与碱金属(Li +,Na +和K +)或碱土金属(Mg 2 +,Ca 2+和Ba 2+)络合阳离子到阿扎克朗 蓝移的幅度取决于阳离子,质子化使ca的变化最大。100纳米阳离子log K = 1-4范围内的结合常数在很大程度上取决于金属的身份阳离子。质子化或阳离子络合导致大多数氮杂冠和L的1 H NMR共振中的下场偏移配体 质子,其大小与UV-Vis波段的蓝移相关;氮杂皇冠的位移1 H NMR共振报告了不同金属如何阳离子 与