Vinylic nucleophilic substitution in functionalized 2-vinylpyrroles: a route to a new family of stable enols
作者:Boris A. Trofimov、Olga V. Petrova、Lyubov' N. Sobenina、Vladislav N. Drichkov、Al'bina I. Mikhaleva、Igor' A. Ushakov、Ol'ga A. Tarasova、Olga N. Kazheva、Anatolii N. Chekhlov、Oleg A. Dyachenko
DOI:10.1016/j.tet.2006.02.009
日期:2006.4
2-(2-Cyano-1-ethylthioethenyl)pyrroles easy exchange their ethylthio group for hydroxyl (NaOH, H2O–methanol, 40–45 °C, 1 h) to give 2-(2-cyano-1-hydroxyethenyl)pyrroles, a new family of stable enols, in 50–94% yields. The vinylic nucleophilic substitution proceeds at the double bond of both the starting pyrroles and their cyclic isomers, 3-iminopyrrolizines. X-ray structure analysis and NMR spectra show the enols
2-(2-氰基-1-乙基硫乙烯基)吡咯易于将其乙硫基交换为羟基(NaOH,H 2 O-甲醇,40-45°C,1小时),得到2-(2-氰基-1-羟基乙烯基)吡咯类是稳定的烯醇类新家族,收率为50-94%。乙烯基亲核取代在起始吡咯及其环状异构体3-亚氨基吡咯烷酮的双键处进行。X射线结构分析和NMR光谱表明,烯醇通过极强的分子内H键键得以稳定。