One-pot relay reduction–isomerization of β-trifluoromethylated-α,β-unsaturated ketones to chiral β-trifluoromethylated saturated ketones over combined catalysts in aqueous medium
the 4,4,4-trifluorobut-2-en-1-ol system undermetal-freeconditions to afford the corresponding saturated ketones in high to excellent chemical yields using such a convenient and easy-to-handle base as DBU at the toluene refluxing temperature, and utilization of the corresponding optically active substrates unambiguously demonstrated that this transformation proceeded in a highly stereoselective fashion
Base-Catalyzed Stereospecific Isomerization of Electron-Deficient Allylic Alcohols and Ethers through Ion-Pairing
作者:Samuel Martinez-Erro、Amparo Sanz-Marco、Antonio Bermejo Gómez、Ana Vázquez-Romero、Mårten S. G. Ahlquist、Belén Martín-Matute
DOI:10.1021/jacs.6b08350
日期:2016.10.12
between an allylic anion and the conjugate acid of the base results in efficient transfer of chirality. Through this mechanism, stereochemical information contained in the allylic alcohols is transferred to the ketone products. The stereospecific isomerization is also applicable for the first time to allylicethers, yielding synthetically valuable enantioenriched (up to 97% ee) enol ethers.