Asymmetric Cyclopropanation of Olefins Catalyzed by Chiral Cobalt(II)-Binaphthyl Porphyrins
Asymmetric Cyclopropanation of Olefins Catalyzed by Chiral Cobalt(II)-Binaphthyl Porphyrins
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DOI：
10.1021/om800556v
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发表时间：
2008-12-08
期刊：
影响因子：
2.8
通讯作者：
Cenini, Sergio
中科院分区：
文献类型：
--
作者：
Fantauzzi, Simone;Gallo, Emma;Cenini, Sergio
合成了手性联萘卟啉钴配合物，并研究了其催化重氮乙酸乙酯与烯烃的不对称环丙烷化反应。良好的产率和对映选择性（高达90%ee），观察到顺/反比达到11：89。UV-vis和H-1 NMR研究表明，轴向氮配体N-甲基咪唑可能在改变反应的对映选择性方面发挥作用。
Cobalt(II) complexes of chiral bis-binaphthyl porphyrins were prepared, and their catalytic activity in the asymmetric cyclopropanation of alkenes with ethyl diazoacetate was examined. Good yields and enantioselectivities (up to 90% ee) were observed with cis/trans ratios reaching 11:89. UV-vis and H-1 NMR studies suggest that the axial nitrogen ligand N-methylimidazole could play a role in changing the enantioselectivity of the reaction.