Controllable cyclization reactions of 2-(2',3'-allenyl)acetylacetates catalyzed by gold and palladium affording substituted cyclopentene and 4,5-dihydrofuran derivatives with distinct selectivity.
Efficient room-temperature syntheses of cyclopentenes and 4,5-dihydrofurans with different substitution patterns were performed starting from the same materials (i.e., 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 by the steric and electronic effects of the substrates and catalysts.
Jiang
Xuefeng
X
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai, China.
Ma
Xiaojing
X
Zheng
Zilong
Z
Ma
Shengming
S