Microwave-assisted, regioselective, Petasis olefination of unsymmetrical oxalates. Formation of pyruvate-based enol ethers and enamines
作者:Matthew J. Cook、Declan W. Fleming、Timothy Gallagher
DOI:10.1016/j.tetlet.2004.11.070
日期:2005.1
The Petasis olefination of unsymmetrical oxalates and oxalate monoesters/monoamides (tert-BuO2CC(O)X, where X = OR, NR2) is highly regioselective and provides pyruvate-based enolether and enamine derivatives. The olefination step occurs under conventional thermal conditions, but is dramatically improved––shorter reaction times and higher yields––when promoted by microwave irradiation.
Silver‐Catalyzed Carbofluorination of Olefins and α‐Fluoroolefins with Carbamoyl Radicals
作者:Émilie Vincent、Julien Brioche
DOI:10.1002/chem.202401419
日期:2024.7.5
A combination of silver oxide (Ag2O) catalyst, potassium persulfate (K2S2O8) and SelectfluorTM was identified to perform radical carbofluorination reactions of olefin and α-fluoroolefin substrates with carbamoyl radicals generated in situ from sodium oxamate salts. Both transformations proceed under mild conditions and provide respectively a straightforward access to β-fluoroamides and β,β-difluoroamides
氧化银 (Ag 2 O) 催化剂、过硫酸钾 (K 2 S 2 O 8 ) 和 Selectflor TM 的组合被确定可利用草酸钠盐原位产生的氨基甲酰基自由基进行烯烃和α-氟烯烃底物的自由基碳氟化反应。两种转化均在温和条件下进行,并分别提供了直接获得β-氟酰胺和β , β-二氟酰胺的途径。