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
Expansion of annulation of allenoates with trifluoroketones: Synthesis of trifluoromethylated dihydropyrans
作者:Tong Wang、Yanpeng Liu、Jinyi Xu
DOI:10.1080/00397911.2017.1402348
日期:2020.2.1
Abstract The DABCO-catalyzed [2 + 2] annulation of allenoates with trifluoroketones could be expanded to [4 + 2] annulation to synthesize trifluoromethylated dihydropyrans with trifluoromethyl oxadienes as the electrophilic annulation partners. GRAPHICAL ABSTRACT
Chiral Brønsted acid-catalyzed regio- and enantioselective arylation of α,β-unsaturated trifluoromethyl ketones
作者:Zeng-kai Pei、Yan Zheng、Jing Nie、Jun-An Ma
DOI:10.1016/j.tetlet.2010.06.132
日期:2010.9
The interesting examples of chiral phosphoric acid-catalyzed regio- and enantioselective arylation of alpha,beta-unsaturated trifluoromethyl ketones were reported. The reaction proceeded well and the desired products were obtained in good yields (up to 99%) with moderate to good enantioselectivities (up to 88% ee). Several desired products were obtained with excellent optical purities after a single recrystallization. Subsequent reduction of enantiopure products with NaBH4 afforded two diastereomers of chiral trifluoromethyl-substituted secondary alcohols with high enantioselectivities (98% ee). (C) 2010 Elsevier Ltd. All rights reserved.