Synthesis of Aminocyclobutanes through Ring Expansion of <i>N</i>-Vinyl-β-Lactams
                                
                                    
                                        作者:Lawrence L. W. Cheung、Andrei K. Yudin                                    
                                    
                                        DOI:10.1021/ol900118d
                                    
                                    
                                        日期:2009.3.19
                                    
                                    Both eight-membered enamide rings and fused [4.2.0]aminocyclobutane-containing delta-lactams can be accessed from N-vinyl-beta-lactams. The eight-membered rings are made through a [3,3] sigmatropic rearrangement. At elevated temperature, the eight-membered lactam undergoes electrocyclization to furnish fused cyclobutane delta-lactams in a diastereoselective manner.