The Influence of Perfluorinated Substituents on the Nucleophilic Reactivities of Silyl Enol Ethers
作者:Hans A. Laub、Daniel Gladow、Hans-Ulrich Reissig、Herbert Mayr
DOI:10.1021/ol301766w
日期:2012.8.3
The fluorinated trimethylsilyl enol ethers 3a–c were synthesized, and the kinetics of their reactions with the benzhydrylium ions 4 was studied by UV–vis spectroscopy in dichloromethane. Comparison with nonfluorinated analogues shows that replacement of CH3 by CF3 reduces the nucleophilic reactivity by 8 orders of magnitude, while the exchange of C6H5 by C6F5 retards the reactions by 4.5 orders of
合成了氟化的三甲基甲硅烷基烯醇醚3a – c,并通过在二氯甲烷中的紫外-可见光谱研究了它们与苯甲基铵离子4的反应动力学。与非氟化类似物的比较表明,用CF 3取代CH 3可使亲核反应性降低8个数量级,而用C 6 F 5交换C 6 H 5则使反应延迟4.5个数量级。