• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Excited-state proton transfer from pyranine to acetate in gamma-cyclodextrin and hydroxypropyl gamma-cyclodextrin
【24h】

Excited-state proton transfer from pyranine to acetate in gamma-cyclodextrin and hydroxypropyl gamma-cyclodextrin

机译：γ-环糊精和羟丙基γ-环糊精中吡喃从兴奋态质子到乙酸的转移

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Excited-state proton transfer (ESPT) from pyranine (8-hydroxypyrene-1,3,6-trisulfonate, HPTS) to acetate has been studied by picosecond and femtosecond emission spectroscopy in gamma-cyclodextrin (gamma-CD) and 2-hydroxypropyl-gamma-cyclodextrin (HP-gamma-CD) cavities. In both the CDs, ESPT from HPTS to acetate is found to be very much slower (90 and 200 ps) than that in bulk water (0.15 and 6 ps). From molecular modeling, it is shown that in the cyclodextrin cavity the acetate is separated from the OH group of HPTS by water bridges. As a result, proton transfer in the cavity requires rearrangement of the hydrogen-bond network involving the cyclodextrin. This is responsible for the marked slowdown of ESPT. ESPT of HPTS in substituted gamma-CD is found to be slower than that in the unsubstituted one. This is attributed to the hydroxypropyl groups, which prevent close approach of acetate to HPTS.
机译：已通过皮秒和飞秒发射光谱在γ-环糊精（γ-CD）和2-羟丙基-丙氨酸中研究了吡喃（8-羟基py-1,3,6-三磺酸盐，HPTS）从激发态的质子转移（ESPT） γ-环糊精（HP-γ-CD）腔。在这两种CD中，发现从HPTS到乙酸盐的ESPT速度（分别为90和200 ps）比散装水（0.15和6 ps）要慢得多。从分子模型可以看出，在环糊精腔中，乙酸酯通过水桥与HPTS的OH基团分离。结果，质子在腔中的转移需要重排涉及环糊精的氢键网络。这是导致ESPT明显下降的原因。发现HPTS在取代的γ-CD中的ESPT慢于未取代的γ-CD。这归因于羟丙基基团，它阻止了乙酸盐接近HPTS。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号