Copper(I)−Homoscorpionate Catalysts for the Preferential, Kinetically Controlled Cis Cyclopropanation of α-Olefins with Ethyl Diazoacetate
作者:M. Mar Díaz-Requejo、Ana Caballero、Tomás R. Belderraín、M. Carmen Nicasio、Swiatoslaw Trofimenko、Pedro J. Pérez
DOI:10.1021/ja011895y
日期:2002.2.1
In situ prepared copper catalysts Tp(X)Cu (Tp(X) = homoscorpionate) catalyze the olefin cyclopropanation reaction using ethyl diazoacetate as the carbene source. Very high values of both activity and diastereoselectivity toward the cis isomer have been obtained for styrene, alpha-methylstyrene, 1-hexene, 1-octene, vinyl acetate, n-butyl vinyl ether, 2,5-dimethyl-2,4-hexadiene, and 3,3-dimethyl-1-butene
原位制备的铜催化剂 Tp(X)Cu (Tp(X) = homoscorpionate) 使用重氮乙酸乙酯作为碳烯源催化烯烃环丙烷化反应。对于苯乙烯、α-甲基苯乙烯、1-己烯、1-辛烯、乙酸乙烯酯、正丁基乙烯基醚、2,5-二甲基-2,4-己二烯,已经获得了非常高的顺式异构体活性和非对映选择性值和 3,3-二甲基-1-丁烯。温度对非对映选择性的影响在 -10 到 +30 摄氏度的范围内几乎可以忽略不计。动力学研究使我们能够提出同型配体可能在催化过程中以二联体形式起作用。这种转化似乎是在动力学控制下进行的,其中顺式异构体的形成将控制反应速率。