芳基硼酸与芳香卤化物的缩合反应

研究了一种新的芳基—芳基偶合反应,取代芳基硼酸与芳香卤化物在零价钯络合物的催化下顺利地发生芳香偶合反应,对一系列在芳环上有推电子取代基的化合物的考察表明,芳香卤化物上的取代基的电子效应不影响偶合反应,它们处于邻位时,也不产生位阻效应,因此,本偶合反应在合成联芳香化合物中有广泛的应用前景。本文也探讨了中间体的合成及偶合反应的条件。

THE CONDENSATION OF ARYLBORONIC ACIDS WITH VARIOUS SUBSTITUTED PHENYLBROMIDES

The article studied a novel aryl-aryl coupling reaction. It stated that nnder the catalysis of tetra( triphenyl phosphine ) pal ladium ( 0 ),subs ti tu- ted arylboronic acids were smoothly reacted with bromobenzenes to carry out the cross-coupling reaction. Biaryls could be produced as expected in the reaction of arylboronic acid with bromobenzene, both of which were substituted by electron-donating groups in various positions,as shown in Table 1. No electronic and/or steric effects could obviouslybe detected in these coupling reactions. The physical and spectoscopic data of coupling products were listed in Table 2. From above results, we conclude that this reactbon would be widely applied to the synthesis of biaryl compounds. Moreover, reaction conditions in synthesis of intermediates and in copling were also studied.