Phosphine-Catalyzed [3 + 2] Cycloaddition of Sulfamate-Derived Cyclic Imines with Allenoate: Synthesis of Sulfamate-Fused Dihydropyrroles
                                
                                    
                                        作者:Hao Yu、Lei Zhang、Zhilin Yang、Zhen Li、Yan Zhao、Yumei Xiao、Hongchao Guo                                    
                                    
                                        DOI:10.1021/jo401107v
                                    
                                    
                                        日期:2013.9.6
                                    
                                    Ph3P-catalyzed [3 + 2] cycloaddition reaction of sulfamate-derived cyclic;mines with allenoate has been developed, affording sulfamate-fused dihydropyrroles under very mild conditions in high yields. Using amino acid-based bifunctional phosphine as chiral catalyst, its asymmetric variant provided the corresponding products in good yields with moderate to excellent enantiomeric excesses (up to 91% yield and up to 98% ee). Subsequent transformations of the heterocyclic products gave various pharmaceutically attractive compounds.