Palladium/P,O-Ligand-Catalyzed Suzuki Cross-Coupling Reactions of Arylboronic Acids and Aryl Chlorides. Isolation and Structural Characterization of (P,O)-Pd(dba) Complex
作者:Xiaohong Bei、Howard W. Turner、W. Henry Weinberg、Anil S. Guram、Jeffrey L. Petersen
DOI:10.1021/jo990805t
日期:1999.9.1
palladium/ligand-catalyzed Suzuki reactions. The 2-(2'-dicyclohexylphosphinophenyl)-2-methyl-1,3-dioxolane (ligand 1) in combination with Pd(dba)(2) affords an efficient catalyst for general Suzuki reactions of a wide variety of arylboronic acids and aryl chlorides, bromides, and iodides to afford the desired biaryl products in high isolated yields. Arylboronic acids and aryl chlorides containing electron-poor
研究了苯基主链衍生的P,O-配体1和2在钯/配体催化的Suzuki反应中作为配体的作用。2-(2'-二环己基膦基苯基)-2-甲基-1,3-二氧戊环(配体1)与Pd(dba)(2)结合提供了一种有效的催化剂,用于各种芳基硼酸和芳基的一般Suzuki反应氯化物,溴化物和碘化物,以较高的分离收率得到所需的联芳基产物。含有贫电子,富电子和邻位取代基的芳基硼酸和芳基氯化物有效参与。相反,发现在相似条件下结构相关的配体2-(2'-二环己基膦基苯基)-1,3-二氧戊环(配体2)效率较低。配体1与Pd(dba)(2)的反应得到复合物LPd(dba)(14,L = 1)。配合物14的NMR光谱和X射线晶体学数据确定,配体1在配合物14中起P,O螯合配体的作用。配体2(2当量)与Pd(dba)(2)和过量的4- (t)()Bu-C(6)H(4)Br或Pd [P(o-tolyl)(3)](4-(t)()Bu-C(6)H