A highly diastereoselective three-component inverse-electron-demand aza DielsâAlder reaction assisted by per(poly)fluoro-alkanesulfinamides is presented, providing a broad spectrum of highly functionalized piperidine derivatives with excellent endo/exo and facial diastereoselectivities. The electron-withdrawing perfluoroalkyl groups are crucial for the success of this reaction under mild conditions and facilitate monitoring the process and stereoselectivities of the reaction. The synthetic potential of these cycloadducts is also highlighted.
The first enantioselective Michael addition of alpha-cyanoketones to alpha,beta-unsaturated trifluoromethyl ketones using a novel piperazine-thiourea catalyst was described. The resulting alpha-trifluoromethyldihydropyrans were obtained in high yields and with up to 95% ee within a short reaction time. A useful transformation of the chiral adduct was also illustrated.
One-Pot Sequential Multistep Transformation of α,β-Unsaturated Trifluoromethyl Ketones: Facile Synthesis of Trifluoromethylated 2-Pyridones
作者:Fa-Guang Zhang、Jun-An Ma、Ning Lv、Yi-Qiang Tian
DOI:10.1055/s-0037-1612077
日期:2019.3
A one-pottransformation of α,β-unsaturated trifluoromethyl ketones with 2-(phenylsulfinyl)acetamide to give trifluoromethylated 2-pyridones is realized. The reaction proceeds under mild conditions and involves multiple steps in an expeditious and controlled sequence to provide efficient access to a broad range of trifluoromethylated 2-pyridones in moderate to high yields. Moreover, further synthetic
Tandem sequential catalytic enantioselective synthesis of highly-functionalised tetrahydroindolizine derivatives
作者:Shuyue Zhang、Mark D. Greenhalgh、Alexandra M. Z. Slawin、Andrew D. Smith
DOI:10.1039/d0sc00432d
日期:——
An isothiourea-catalysed enantioselectivesynthesis of novel tetrahydroindolizine derivatives is reported through a one-pot tandem sequential process. The application of 2-(pyrrol-1-yl)acetic acid in combination with either a trifluoromethyl enone or an α-keto-β,γ-unsaturated ester in an enantioselective Michael addition–lactonisation process, followed by in situ ring-opening and cyclisation, led to
Tandem stereoselective synthesis of new trifluoromethylated pyranopyrazoles
作者:Jian Wang、Guan-Bo Huang、Li-Jun Yang、Feng Li、Jing Nie、Jun-An Ma
DOI:10.1016/j.jfluchem.2014.10.008
日期:2015.3
trifluoromethyl ketones is described. The notable features of this tandem process are its operational simplicity, easily accessible starting materials, and mild reaction conditions. The corresponding trifluoromethylated pyranopyrazoles were obtained in excellent yields (85–99%) with good to excellent diastereoselectivities (6:1–30:1). In addition, the stereochemical assignment of the major isomer by X-ray crystallographic