Expeditious Synthesis of Phenanthrenes via CuBr<sub>2</sub>-Catalyzed Coupling of Terminal Alkynes and <i>N-</i>Tosylhydrazones Derived from <i>O</i>-Formyl Biphenyls
                                
                                    
                                        作者:Fei Ye、Yi Shi、Lei Zhou、Qing Xiao、Yan Zhang、Jianbo Wang                                    
                                    
                                        DOI:10.1021/ol201788v
                                    
                                    
                                        日期:2011.10.7
                                    
                                    A new method for the synthesis of phenanthrenes via ligand-free CuBr2-catalyzed coupling/cyclization of terminal alkynes with N-tosylhydrazones derived from o-formyl biphenyls has been developed. This new synthesis has wide range of functional group compatibility.