Stereoselective generation of cis-2-lithio-3-CF3-oxirane via CF3-substituted β-oxido carbenoids. Highly stereoselective synthesis of CF3-substituted tri- and tetrasubstituted oxiranes and tetrasubstituted alkenes
1,1-trifluoropropan-2-ols with organolithium reagents R2Li in THF at −98°C stereoselectively produces 2,3-disubstituted 2-lithio-3-trifluoromethyloxiranes with Li and CF3cis. The reagents react with electrophiles El-X or organoboranes R3BR2 to give CF3-containingtri- and tetrasubstitutedoxiranes or tetrasubstitutedalkenes, respectively, with high diastereoselectivities.
A novel synthesis of tetrasubstituted fluoroolefins via eliminative nucleophilic addition of β-retophosphonium salts
作者:Yanchang Shen、Weiming Qiu
DOI:10.1016/s0040-4039(00)95753-8
日期:1987.1
A novel one-pot synthesis of tetrasubstituted fluoroolefins via eliminative nucleophilic addition of β-ketophosphonium salts leading to the union of four fragements is described.
作者:Gino Occhialini、Vignesh Palani、Alison E. Wendlandt
DOI:10.1021/jacs.1c12043
日期:2022.1.12
The positional isomerization of C═C double bonds is a powerful strategy for the interconversion of alkene regioisomers. However, existing methods provide access to thermodynamically more stable isomers from less stable starting materials. Here, we report the discovery of a dual catalyst system that promotes contra-thermodynamic positional alkeneisomerization under photochemical irradiation, providing