• 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 >Proton-transfer reaction of 4-methyl 2,6-diformyl phenol in cyclodextrin nanocage
【24h】

Proton-transfer reaction of 4-methyl 2,6-diformyl phenol in cyclodextrin nanocage

机译：4-甲基2,6-二甲酰基苯酚在环糊精纳米笼中的质子转移反应

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

We report here on the steady-state and time-resolved fluorescence studies on proton-transfer (PT) reaction of 4-methyl 2,6-diformyl phenol (MFOH) in confined nanocavities in three solvents, dimethyl sulfoxide (DMSO), dimethyl formamide (DMF), and water. Though DMSO and DMF individually interact with MFOH in a similar fashion, their modes of interaction get significantly modified in the presence of cyclodextrin (CD) nanocages. In DMSO, in the ground state, the solvated molecular anion of MFOH forms 1:1 inclusion complex with beta- or gamma-CD and attains greater stability compared to the normal form. In DMF, the solvated molecular anion gets converted to the H-bonded complex within the CD cavity resulting in a 50-nm blue shift in the absorption spectra. In the excited state, the anionic species gets more stabilized in DMSO while in DMF it is significantly destabilized in the presence of CDs. However, in case of water, MFOH gets trapped inside the water cages so that the CDs fail to complex with it effectively. There are also no changes in the excited-state lifetimes in water in the presence of CDs, but in case of DMSO and DMF, because of restricted rotation of the formyl group within the CD cavity, the contribution of the shorter lifetime components reduce significantly increasing the larger components. Some theoretical calculations at the AM1 level of approximation have also been carried out to demonstrate how the dipolar nature of the solvent influences excited-state PT in confined media.
机译：我们在这里报告在受限的纳米腔中于三种溶剂，二甲基亚砜（DMSO），二甲基甲酰胺中的4-甲基2,6-二甲酰基苯酚（MFOH）的质子转移（PT）反应的稳态和时间分辨荧光研究（DMF）和水。尽管DMSO和DMF分别以类似的方式与MFOH相互作用，但在存在环糊精（CD）纳米笼子的情况下，它们的相互作用方式得到了显着改变。在DMSO中，处于基态时，MFOH的溶剂化分子阴离子与β-或γ-CD形成1：1的包合物，与正常形式相比具有更大的稳定性。在DMF中，溶剂化的分子阴离子在CD腔内转化为H键结合的络合物，导致吸收光谱发生50 nm蓝移。在激发态下，阴离子物质在DMSO中变得更加稳定，而在DMF中则在CD的存在下明显不稳定。但是，在水的情况下，MFOH被困在水笼中，因此CD无法有效地与其络合。在存在CD的情况下，水中的激发态寿命也没有变化，但是在DMSO和DMF的情况下，由于CD腔内甲酰基的旋转受到限制，较短寿命的组分的贡献显着降低，较大的组件。还已经在AM1近似水平上进行了一些理论计算，以证明溶剂的偶极性质如何影响受限介质中的激发态PT。

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