Enantiopure 2-aryl-2-methyl cyclopentanones by an asymmetric chelation-controlled Heck reaction using aryl bromides: increased preparative scope and effect of ring size on reactivity and selectivity
作者:Gopal K. Datta、Patrik Nordeman、Jakob Dackenberg、Peter Nilsson、Anders Hallberg、Mats Larhed
DOI:10.1016/j.tetasy.2008.04.004
日期:2008.5
2-aryl-2-methyl cyclopentanones were obtained in 85–94% ee via Pd(0)-catalyzed chelation-controlled asymmetric arylation of a cyclopentenyl ether with aryl bromides and subsequent hydrolysis. Two new cyclohexenyl ethers were synthesized and evaluated as Heck substrates with both aryl iodides and bromides under different reaction conditions. Arylations of the six-membered vinyl ether 1-methyl-2-(S)-(cyclohex
通过Pd(0)催化的环戊烯基醚与芳基溴化物的螯合控制的不对称芳基化反应和随后的水解反应,可在85-94%ee中获得季铵化的2-芳基-2-甲基环戊酮。合成了两种新的环己烯基醚,并在不同反应条件下将其与芳基碘化物和溴化物一起作为Heck底物进行了评估。六元乙烯基醚1-甲基-2-(S)-(环己基-1-烯氧基甲基)-吡咯烷与芳基溴化物的芳基化反应是通过t - Bu 3 P促进的钯催化使用经典或微波加热实现的。分离出的Heck产物还具有很高的非对映选择性(94-98%de)。