在原位生成的次膦酸酯配体t Bu 2 POR(R = n Bu,n Pr,Et或Me)存在下,开发了一种用于(杂)芳基溴的烷氧羰基化的有效方法。为此目的,在不同醇存在下,将可商购的t Bu 2 PC1用作预配体。首次开发了与两种醇的交叉偶联反应-一种生成配体,另一种用作底物。通过这种方法,可以以更有效的方式进行配体优化,并且可以以良好的产率和选择性获得所需的产物。
Ligand-Free Copper(I)-Catalyzed Benzylic Acyloxylation of 2-Alkylpyridines under Aerobic Conditions
作者:Li Cheng、Yuqian Sun、Wenrong Wang、Changsheng Yao、Tuan-Jie Li
DOI:10.1021/acs.joc.8b02794
日期:2019.3.15
A ligand-free copper(I)-catalyzed benzylic acyloxylation of 2-alkylpyridines with carboxylic acids was realized by using 1.0 atm of O2 as a green oxidant. The transformation provided a facile access to a wide range of N-heterocyclic esters through C–O bond formation, with broad substrate scope and good functional group tolerance. Preliminary mechanistic investigations showed that this protocol included
range of organic electrophiles with chelated formate is reported to afford aryl and alkenyl esters by the simultaneous employment of Ru and Pd catalyst, in which ruthenium first promotes chelation-accelerated decarbonylation of formate to release CO and carbinol that are presumed to be transferred, still chelated to Ru, into Pd catalyst, which catalyzes alkoxycarbonylation of the organic electrophiles
nickel-catalyzed alkoxycarbonylation of aromatic iodides with alcoholsunder atmospheric pressure of carbonmonoxide is presented here. This operationally simple protocol allows the facile synthesis of (hetero)aromatic esters, exhibiting broad substrate scope with excellent functional group tolerance. Various primary and secondary aliphatic alcohols as well as phenols are suitable for this transformation