Intermolecular and Selective Synthesis of 2,4,5-Trisubstituted Oxazoles by a Gold-Catalyzed Formal [3+2] Cycloaddition
作者:Paul W. Davies、Alex Cremonesi、Lidia Dumitrescu
DOI:10.1002/anie.201103563
日期:2011.9.12
Oxazole new world: A gold‐catalyzed intermolecular reaction of pyridine‐N‐aminides with ynamides can be used to prepare trisubstituted 1,3‐oxazoles with a variety of functional groups. This formal [3+2] cycloaddition employs robust conjugated N‐ylides as N‐nucleophilic N‐acyl nitrene equivalents for a highly chemoselective and regioselective addition across electron‐rich CC triple bonds.
Practical conversion of <i>gem</i>-difluorocyclopropenes for the chemodivergent assembly of fluorinated heterocyclic frameworks
作者:Dongping Pan、Fu-Xiaomin Liu、Zhongyi Zeng、Junwei Ye、Ying Cai、Shengdong Wang、Zhi Zhou、Wei Yi
DOI:10.1039/d3gc03203e
日期:——
diverse fluorinatedheterocyclic frameworks including cyclopropapyrazolopyridines, indolizines, 2-fluoro-3-aryl-3-(heteroaryl)acrylamides etc. These conversions feature ultrasonic vibration-assisted solvent-free 1,3-dipolar cycloaddition, photo-induced rearrangement and mild reduction, providing a highly efficient synthetic route for the assembly of intriguing fluorine-containing compounds with good