Steric effects on controlling of photoinduced electron transfer action of anthracene modified benzo-15-crown-5 by complexation with Mg2+ and Ca2+
作者:Jeongsik Kim、Yoshikazu Oka、Tatsuya Morozumi、Eun Wha Choi、Hiroshi Nakamura
DOI:10.1016/j.tet.2011.05.042
日期:2011.7
intramolecular charge/electron transfer process. After the complex formation with Mg2+ and Ca2+, however, only the 2-position analogue gave a fluorescence ‘on’ response by inhibiting the photoinduced electron transfer. Because 2-positioned anthracene was free from steric hindrance of the crown ether ring, a strongly bent complex structure was formed with Mg2+ and Ca2+, which induced a breakdown of π-conjugation
合成了基于蒽-冠醚的化学传感器,该传感器通过蒽环的1、2或9位的酰胺键连接。使用荧光,紫外和1 H NMR光谱研究了它们与乙腈中碱土金属离子的络合行为。在没有金属离子的情况下,由于分子内电荷/电子转移过程,所有化合物仅显示出非常小的荧光发射(荧光“关闭”状态)。但是,在与Mg 2+和Ca 2+形成络合物后,只有2位类似物通过抑制光致电子转移而发出荧光“ on”响应。由于2位蒽没有冠醚环的位阻,因此Mg形成了强烈弯曲的复合结构2+和Ca 2+,它们导致酰胺部分和苯环之间的π共轭分解。