Controllable Cyclization Reactions of 2??(2′, 3′??Allenyl) acetylacetates Catalyzed by Gold and Palladium Affording Substituted Cyclopentene and 4, 5??Dihydrofuran …
X Jiang, X Ma, Z Zheng, S Ma
文献索引:Jiang, Xuefeng; Ma, Xiaojing; Zheng, Zilong; Ma, Shengming Chemistry - A European Journal, 2008 , vol. 14, # 28 p. 8572 - 8578
Abstract Efficient room-temperature syntheses of cyclopentenes and 4, 5-dihydrofurans with different substitution patterns were performed starting from the same materials (ie, 2-(2′, 3′-allenyl) acetylacetates). Depending on the choice of metal catalyst, the Au-catalyzed reaction afforded C-attack-5-endo cyclization products 2, whereas the Pd-catalyzed one led to the formation of O-attack-5-exo cyclization products 3. The selectivity may be explained ...