Cu-Catalyzed Aerobic Oxidative Three-Component Coupling Route to <i>N</i>-Sulfonyl Amidines via an Ynamine Intermediate
                                
                                    
                                        作者:Jinho Kim、Shannon S. Stahl                                    
                                    
                                        DOI:10.1021/jo5029198
                                    
                                    
                                        日期:2015.2.20
                                    
                                    Cu-catalyzed aerobic oxidative three-component coupling of a terminal alkyne, secondary amine, and sulfonamide enables efficient synthesis of amidines. The use of Cu(OTf)(2) (5 mol %) produces amidines selectively without GlaserHay alkyne homocoupling products. Preliminary studies suggest that the reaction pathway involves initial oxidative coupling of the terminal alkyne with the secondary amine, followed by hydroamidation of the ynamine intermediate with the sulfonamide.