Conservation of absolute configuration in the acyclic rhodium-catalyzed allylic alkylation reaction:: Evidence for an enyl (σ+π) organorhodium intermediate
Conservation of absolute configuration in the acyclic rhodium-catalyzed allylic alkylation reaction:: Evidence for an enyl (σ+π) organorhodium intermediate
复制标题
DOI：
10.1021/ja980030q
复制
发表时间：
1998-06-10
影响因子：
15
通讯作者：
Nelson, JD
中科院分区：
文献类型：
--
作者：
Evans, PA;Nelson, JD
烯丙基烷基化反应是形成碳-碳键的有效方法。1然而，尽管已经采用了广泛的底物和有机金属络合物，但还没有出现保持绝对构型的一般程序。2，3我们最近证明了Wilkinson的催化剂[Rh(PPh3)3CL]可以被原位修饰，以提供催化活性物种，促进一系列外消旋无环烯丙基碳酸酯的烯丙基烷基化反应，产率高，选择性好，有利于更多的取代产物。4在这篇通讯中，我们描述了第一个例子，在不对称催化下，富含对映体的无环烯丙基碳酸酯1的不对称烯丙基烷基化反应基本上完全保持了绝对构型(式1)。
The allylic alkylation reaction represents a powerful method for carbon-carbon bond formation. 1 However, despite the wide range of substrates and organometallic complexes that have been employed, a general procedure for the retention of absolute configuration has not been forthcoming. 2, 3 We recently demonstrated that Wilkinson’s catalyst,[Rh (PPh3) 3Cl], may be modified in situ to furnish a catalytically active species that facilitates the allylic alkylation of a series of racemic acyclic allylic carbonates in high yield and with excellent selectivity, favoring the more substituted product. 4 In this communication, we describe the first example of the asymmetric rhodium-catalyzed allylic alkylation of an enantiomerically enriched acyclic allylic carbonate 1, with essentially complete retention of absolute configuration (eq 1).