An Effective Method for the Construction of Esters Using Cs2CO3 as Oxygen Source
摘要:
An effective method for the construction of esters from acyl chloride and halohydrocarbon using Cs2CO3 as an oxygen source was achieved for the first time. The methodology has a wide scope of substrates and can be scaled up. The study of a preliminary reaction mechanism demonstrated that the 0 in the products comes from Cs2CO3 and this esterification proceeds through a free radical reaction. It was also found that CO2 can also be used in this esterification reaction as an oxygen source.
Palladium(II)-Catalyzed<i>ortho</i>Alkylation of Benzoic Acids with Alkyl Halides
作者:Yang-Hui Zhang、Bing-Feng Shi、Jin-Quan Yu
DOI:10.1002/anie.200902262
日期:2009.8.3
Outsmarting the competition: In the PdII‐catalyzed reaction of benzoates with alkyl halides, an aryl CH bond is activated before the competitive alkylation of the carboxylate anion can takes place. The alkylation reaction was followed by an intramolecular lactonization to give broadly useful γ‐ and δ‐benzolactones (see scheme).
战胜竞争:在 Pd II催化的苯甲酸盐与卤代烷的反应中,芳基 C H 键在羧酸根阴离子的竞争性烷基化发生之前被激活。烷基化反应后进行分子内内酯化,得到广泛有用的 γ- 和 δ-苯内酯(参见方案)。