Synthesis of some substituted 5,6,11,12-tetrahydro-dibenzo[a,e]cyclooctene derivatives through the intermediacy of tricarbonyl(η6-arene)chromium complexes
作者:A.Moshtaghi Zenouz
DOI:10.1016/j.tetlet.2004.02.050
日期:2004.3
5,6,11,12-Tetrahydrodibenzo[a,e]cyclooctene derivatives with α- and β-substituents are readily accessible from [Cr(CO)3(5,6,11,12-tetrahydrodibenzo[a,e]cyclooctene)] 2 via a two-step sequence, which involves addition of a nucleophile and oxidation of the intermediate anionic cyclohexadienyl complex. Nucleophiles used included LiCMe2CN (A), LiCH2CN (B), and (C). The results show that the primary carbanion
从[Cr(CO)3(5,6,11,12-四氢二苯并[ a,e ]环辛烯)可以容易地获得具有α-和β-取代基的5,6,11,12-四氢二苯并[ a,e ]环辛烯衍生物] 2通过两步序列进行,这涉及亲核试剂的添加和中间阴离子环己二烯基复合物的氧化。所用的亲核试剂包括LiCMe 2 CN(A),LiCH 2 CN(B)和(C)。结果表明,主碳负离子LiCH 2CN和S稳定的碳负离子可生成α-和β-取代产物的混合物,在两种情况下,α-异构体都是主要异构体,而叔碳负离子LiCMe 2 CN则具有相反的区域选择性。