Isoxazole‐Embedded Allylic Zinc Reagent for the Diastereoselective Preparation of Highly Functionalized Aldol‐Type Derivatives Bearing a Stereocontrolled Quaternary Center
作者:Lydia Klier、Coura R. Diène、Manuel Schickinger、Albrecht Metzger、Andreas J. Wagner、Konstantin Karaghiosoff、Ilan Marek、Paul Knochel
DOI:10.1002/chem.201402733
日期:2014.10.20
Highly functionalized aldol‐type products bearing a β‐quaternary center and a stereoselectively controlled γ‐hydroxy function are readily prepared by the diastereoselective addition of an allylic zinc reagent embedded in an isoxazole ring to various aromatic and heteroaromatic aldehydes, in the presence of Lewis acids, such as MgCl2 or LaCl3⋅2 LiCl. After reductive cleavage of the NO bond by using
在路易斯酸的存在下,通过将对异恶唑环中嵌入的烯丙基锌试剂非对映选择性地添加到各种芳香族和杂芳香族醛中,可以轻松制备具有β-季中心和立体选择性控制的γ-羟基功能的高度官能化的醛醇型产品。如的MgCl 2或的LaCl 3 ⋅2的LiCl。用Fe,NH 4 Cl还原N键后,观察到带有立体控制的β-季中心和γ-羟基的羟醛型产物。在BF 3· OEt 2存在下,异恶唑基甲基锌试剂对其他亲电子试剂(如酰氯,芳基和烯丙基卤化物)以及醛的苄基反应活性 也进行了描述。