The Grignard Reaction of Cyclodextrin-6-aldehydes Revisited: A Study of the Stereoselectivity Upon Addition of Organometallic Reagents to Aldehydes and Ketones
作者:Emil Lindbäck、You Zhou、Lavinia Marinescu、Christian M. Pedersen、Mikael Bols
DOI:10.1002/ejoc.201000295
日期:——
2 A-G ,3 A-G ,6 B-G -Icosakis-O-benzyl-6 A -O-oxo-β-cyclodextrin was treated with aromatic and aliphatic Grignard reagents to give diastereomeric mixtures of the secondary alcohols with remarkable difference in polarity. Moderate-to-good yields and selectivity were obtained. By oxidizing the secondary alcohols, followed by a second Grignard reaction, good to excellent yields and selectivity of tertiary
2 AG ,3 AG ,6 BG -Icosakis-O-benzyl-6 A -O-oxo-β-环糊精用芳香族和脂肪族格氏试剂处理得到具有显着极性差异的仲醇的非对映异构混合物。获得了中等至良好的产率和选择性。通过氧化仲醇,然后进行第二次格氏反应,可以获得良好至极好的叔醇收率和选择性。显示反应结果的立体化学取决于格氏试剂的添加顺序并且可以有效控制。