Control of Chemical Selectivity by Effect of Shape Similarity between Solute and Solvent Molecules

通过溶质和溶剂分子之间形状相似性的影响来控制化学选择性

• 批准号: 05640613
• 负责人: ENDO Tadashi
• 金额: $ 1.28万
• 依托单位: Aoyama Gakuin University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05640613/
• 关键词: Control Of Chemical Selectivity; Oxidation; Associating Thiol; Shape Similarity; Hydrocarbon; Propyle Alcohol

In order to develop a more "precise" and novel type of method for control of chemical selectivity, we examined correlation of the selectivity and the pattern of temperature dependence of the selectivity in oxidation of a pair of associating thiols (I and II) , each having R^1 or R^2 as a substituent, with shape similarity between substituents of solute and solvent molecules.1. The selectivity (R^1=Ph, R^2=n-C_5H_<11>) was higher in methanol-n-propyl alcohol than in methanol-isopropyl alchol (at 20 and 35ﾟC).2. The selectivity (R^1=Ph, R^2=i-C_5H_<11>) in hydrocarbon-water-n-propyl alcohol (mole fraction of hydrocarbon=0.50) increased in going from cyclohexane, n-hexane, and to isohexane.3. The selectivity (R^1=Ph, R^2=i-C_5H_<11>) exhibited a maximum at ca.35ﾟC in benzene-ethanol (mole fraction of ethanol=0.50) , showed a minimum in isohexane-ethanol, and decreased with temperature in n-hexane-ethanol.4. The selectivity (R^1=cyclo-C_5H_9, R^2=n-C_4H_9) increased with temperature both in methanol-n-butyl alcohol (mole fraction of methanol=0.50) and in methanol-isobutyl alchol.It is evident from these results that (i) the selectivity increases when a substituent of a thiol is similar in shape to that of a solvent molecule and (ii) the pattern of temperature dependance of the selectivity alters markedly with the degree of shape similarity between substituents of solute and solvent molecules. This indicates that shape similarity effect becomes a novel type of method for control of chemical selectivity.

为了开发一种更“精确”和新颖的化学选择性控制方法，我们研究了一对缔合硫醇（I和II）的氧化中选择性的相关性和选择性的温度依赖性模式，每个缔合硫醇均具有R^1或R^2作为取代基，并且溶质和溶剂分子的取代基之间具有形状相似性。甲醇-正丙醇的选择性（R^1=Ph，R^2=n-C_5H_<11>）高于甲醇-异丙醇（20℃和35℃）。2．从环己烷、正己烷到异己烷，烃-水-正丙醇(烃摩尔分数=0.50)的选择性(R^1=Ph，R^2=i-C_5H_<11>)有所增加。 3．苯-乙醇(乙醇摩尔分数=0.50)中的选择性(R^1=Ph,R^2=i-C_5H_<11>)在约35℃时表现出最大值，异己烷-乙醇中表现出最小值，正己烷-乙醇中随温度升高而降低。4．在甲醇-正丁醇（甲醇的摩尔分数=0.50）和甲醇-异丁醇中，选择性（R^1=cyclo-C_5H_9，R^2=n-C_4H_9）随温度增加。从这些结果可以明显看出，（i）当硫醇取代基的形状与溶剂分子的形状相似时，选择性增加；（ii）温度模式 选择性的依赖性随着溶质和溶剂分子的取代基之间的形状相似程度而显着变化。这表明形状相似效应成为一种新型的化学选择性控制方法。