权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

The Study of Generating Stabilized Phenyl Cations by Using New Super-Leaving Groups

利用新型超离去基团生成稳定苯基阳离子的研究

基本信息

批准号：
07640726
负责人：
SONODA Takaaki
金额：
$ 1.47万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07640726/
关键词：
Trifyl-substituted Heteroatom Functional Group Phenyl Cations Structure and reactivity Molecular Orbital Method Calculation Analysis of Substituent effects Solvolysis Reactions Weakly-Coordinating Polyfluorinated Organic Anions 反応性炭素陽イオン中間体

项目摘要

Various alkali metal, alkali-earth metal, and transition metal ions ion-paired with weakly-coordinating polyfluorinated organic anions such as OSO_2CF_3, N (SO_2CF_3) _2, and C (SO_2CF_3) _3 were examined as strong Lewis acids in catalytic Diels-Alder reactions and halochromism of azo-dye compounds in nonpolar organic solvents to investigate the coordinating and leaving abilities of the organic anions.The photosolvolysis of aryl triflates in fluorinated alcohols was proved to proceed via aryl cation intermediates, while the photo-and thermal-solvolysis of aryl ester ArOS (O) (CF_3)=C (SO_2CF_3) _2 gave the products derived from the ArO-S (O) bond cleavage.The experimental relative rate-constant for the dediazoniation reactions of para- and meta-substituted benzenediazonium ions in solution was good correlated with the computational relative stabilizing energy of the corresponding phenyl cations with para- and meta-substituents, respectively. The phenyl cations with electron-donating substituents on meta-position are highly stabilized by novel direct-conjugation with the meta-substituents.Experimental evidences of this novel effect of meta-substituent for stabilizing phenyl cation intermediates in the thermal-solvolysis of the aryl triflate with piperidinyl groups at 3,5-positions were demonstrated : exclusive formation of solvent-substituted products and solvent polar effect in the solvolysis in TFE,HEIP,and aqueous HFIP indicated the S_N1 mechanism of the solvolysis to proceed via ary1 cations highly stabilized by the meta-substituents.

研究了各种碱金属、碱土金属和过渡金属离子与弱配位的多氟有机阴离子OSO_2CF_3、N (SO_2CF_3) _2和C (SO_2CF_3) _3作为强路易斯酸在催化diols - alder反应和偶氮染料化合物在非极性有机溶剂中的变色性能，考察了有机阴离子的配位和离开能力。氟化醇中芳基三氟酸酯的光溶剂解是通过芳基阳离子中间体进行的，而芳基酯ArOS (O) (CF_3)=C (SO_2CF_3) _2的光溶剂解和热溶剂解是由ArO-S (O)键裂解得到的产物。对取代苯二氮离子和间取代苯二氮离子在溶液中脱氮反应的实验相对速率常数分别与对取代基和间取代基对应的苯基阳离子的计算相对稳定能具有良好的相关性。具有给电子取代基的苯基阳离子通过与取代基的直接偶联得到了高稳定性。在3,5位哌替啶基三氟化芳基的热溶剂溶解中，间取代基稳定苯基阳离子中间体的新作用得到了实验证明：在TFE、HEIP和HFIP水溶液中，溶剂溶解中溶剂取代产物的独特形成和溶剂极性效应表明，溶剂溶解的S_N1机制是通过被间取代基高度稳定的ary1阳离子进行的。