To discover new heterogeneous palladium catalyst in organic synthesis, pectin, which was extracted form citrus peel, was used as supporter for the preparation of pectin-supported palladium catalyst. The pectin-supported palladium catalyst was applied to Suzuki cross-coupling reaction between sodium tetraphenylborate and aryl bromides. The results revealed that all four aryl groups of sodium tetraryylborate could be efficiently utilized in the Suzuki cross-coupling reactions in an atom-efficient way in the presence of Et3 N as base in PEG 400/H2 O at 110 ℃ in open air, providing excellent yields of the corresponding functionalized biaryls within 1 h. The present protocol has the advantages highly efficient, high yield, mild condition, short reaction time, as well as the catalyst can be recycled and reused.%以柑橘皮果胶为载体,采用吸附法制备了果胶负载钯催化剂,并将其应用于四苯硼钠与溴代芳烃的交叉偶联反应中.该反应体系以聚乙二醇400(PEG 400)/H2O为反应溶剂,三乙胺为碱,在空气中于110℃反应15～60 min,四苯硼钠中4个苯基均可顺利参与反应,高产率地获得相应的目标化合物.该方法具有条件温和、反应时间短、收率高且催化剂可循环利用等优点.
展开▼
