RUI: The Role of Solvent Density and Solvation on the Enol-Keto Tautomerism in Supercritical Fluid Solvents.

该项目的总体目标是了解溶质和超临界流体（SCFs）溶剂之间的分子相互作用。实验技术和理论方法将应用于研究溶剂密度和溶剂化在烯醇-酮互变异构中的作用。本工作的目的是：1)利用傅里叶变换红外光谱法估计超临界二氧化碳和乙烷中烯醇-酮-互变异构的平衡常数。通过改变温度和压力来调节溶剂的密度，研究密度对烯醇-酮互变异构的影响。2)通过比较超临界二氧化碳和超临界乙烷的互变异构平衡常数，探讨溶剂化的作用。二氧化碳的四轴矩可能导致与溶质（单羰基化合物和二羰基化合物）的化学相互作用。3)采用晶格流体氢键模型确定SCF溶剂中互变异构的理论平衡常数。建模工作将以定量的方式反映溶质和溶剂之间的相互作用。这项拟议研究的意义在于，它可能会扩大SCFs作为反应手段和萃取介质的潜在用途。这是基于我们对溶质和溶剂之间分子相互作用的理解，这对于SCF溶剂在生物技术、纳米颗粒和复合材料、废物修复以及多功能聚合物的设计和合成等方面的应用至关重要。

The overall objective of the proposed project is to understand the molecular interaction between solute and supercritical fluid (SCFs) solvents. Both experimental techniques and a theoretical approach will be applied to investigate the role of solvent density and solvation in enol-keto tautomerism. The objectives of this work are:1) The enol-keto tautomeric equilibrium constant in supercritical carbon dioxide and ethane will be estimated by using Fourier Transform infrared spectroscopy. The density of solvent will be adjusted by varying the temperature and pressure to investigate the effect of density on enol-keto tautomerism.2) The role of solvation will also be investigated by comparing the tautomeric equilibrium constants in supercritical carbon dioxide with those in supercritical ethane. The quadrapole moment for carbon dioxide may lead to a chemical interaction with solutes (mono- and bicarbonyl compounds).3) Theoretical tautomeric equilibrium constants in SCF solvent will be determined by using the lattice fluid hydrogen bonding model. The modeling work will reflect the interactions between solute and solvent in a quantitative manner. The significance of this proposed research is that it is likely to produce an expansion of the potential uses of SCFs as a means of reaction and as extraction media. This is based on increasing our understanding of the molecular interactions between solute and solvent, which is critical for the application of SCF solvents towards biotechnology, nano-particle and composite materials, remediation of waste materials, and the design and synthesis of multi-functional polymers.