Regiocontrolled Halohydroxylations of Bicyclic Vinylidenecyclopropanes: A Versatile Strategy for the Construction of Diverse Highly Functionalized Carbocyclic Scaffolds
作者:Chenliang Su、Jian Cao、Xin Huang、Luling Wu、Xian Huang
DOI:10.1002/chem.201002141
日期:2011.2.1
means of proximal cleavage of the cyclopropane ring. In addition, vinylidenecyclopropanes that bore one aryl group at the cyclopropyl ring reacted with NBS or I2 at room temperature, thereby producing the corresponding divinyl ketones 4 in moderate to good yields with excellent E selectivity. Unexpectedly, 2‐vinylic cyclohex‐2‐enols 6 were generated through a very different distal CC bond cleavage of the
双环vinylidenecyclopropanes导致四种类型的产品的高度选择性halohydroxylations 2,3,4,和6的开发工作。卤代羟基化反应在室温下发生,以55-90%的产率产生具有环-和非对映选择性的环双环产物乙烯基双环[(n +2).1.0]链烷醇2。双环亚乙烯基环丙烷与2.0当量的N-溴代琥珀酰亚胺(NBS)在100°C下反应得到亚烷基双环[(n +2).2.0]烷酮3通过进一步近端环丙烷环的裂解,可得到48-75%的收率。X射线晶体衍射已阐明了两种化合物2和3的结构。当在指定条件下进行双环亚乙烯基环丙烷与N-卤代琥珀酰亚胺(NXS; 3.0当量)的反应以通过近端反应提供各种二乙烯基酮4时,开发了一个有趣的顺序反应,该反应由几个亲电加成和消除反应组成。环丙烷环的断裂。此外,在环丙基环上带有一个芳基的亚乙烯基环丙烷与NBS或I 2反应在室温下,由此以中等至良好的产率