Catalyst-controlled site-selective methylene C–H lactonization of dicarboxylic acids
作者:Hau Sun Sam Chan、Ji-Min Yang、Jin-Quan Yu
DOI:10.1126/science.abq3048
日期:2022.6.24
and γ-methylene carbon-hydrogen (C-H) bonds of free carboxylic acids is a long-standing challenge. Here we show that, with a pair of palladium catalysts assembled with quinoline-pyridone ligands of different chelate ring sizes, it is possible to perform highly site-selective monolactonization reactions with a wide range of dicarboxylic acids, generating structurally diverse and synthetically useful γ-
游离羧酸的β-和γ-亚甲基碳氢(CH)键的催化剂控制的位点选择性活化是一个长期存在的挑战。在这里,我们表明,通过一对由不同螯合环尺寸的喹啉-吡啶酮配体组装的钯催化剂,可以与多种二羧酸进行高度位点选择性的单内酯化反应,产生结构多样且合成上有用的γ-和δ-内酯通过位点选择性β-或γ-亚甲基CH活化。剩余的羧基可作为进一步合成应用的多功能关键,如从丰富的二羧酸中全合成两种天然产物 myrotheciumone A 和pedicellosine 所证明的那样。