Palladium-Catalyzed Cross-Coupling Reactions of Potassium Alkenyltrifluoroborates with Organic Halides in Aqueous Media
作者:Emilio Alacid、Carmen Nájera
DOI:10.1021/jo802356n
日期:2009.3.20
cross-coupled with aryl and heteroaryl bromides using 1 mol % Pd loading of 4-hydroxyacetophenone oxime derived palladacycle or Pd(OAc)2 as precatalysts, K2CO3 as base, and TBAB as additive and water reflux under conventional or microwave heating to afford styrenes, stilbenoids, and alkenylbenzenes. These borates can be cross-coupled diastereoselectively with allyl and benzyl chlorides using KOH as base
乙烯基和烯基三氟硼酸钾与芳基和杂芳基溴化物进行交叉偶联,使用1摩尔%的4-羟基苯乙酮肟衍生的palladacycle或Pd(OAc)2作为Pd的前催化剂,K 2 CO 3在常规或微波加热下,作为碱和TBAB作为添加剂并进行水回流,得到苯乙烯,二苯乙烯类化合物和烯基苯。这些硼酸盐可以在丙酮水(3:2)中,在50°C和0.1 mol%Pd负载下,使用KOH作为碱,与烯丙基氯和苄基氯进行非对映选择性交联,分别得到相应的1,4-二烯和烯丙基芳烃。这些简单的无膦反应条件允许通过萃取分离包含58-105 ppm Pd的产物,在多达五次运行中从水相中回收钯。