Ni ion-containing ionic liquid salt and Ni ion-containing immobilized ionic liquid on silica: Application to Suzuki cross-coupling reactions between chloroarenes and arylboronic acids
Ni ion-containing ionic liquid salt and Ni ion-containing immobilized ionic liquid on silica: Application to Suzuki cross-coupling reactions between chloroarenes and arylboronic acids
复制标题
DOI：
10.1016/j.jcat.2006.06.020
复制
发表时间：
2006-09
影响因子：
7.3
通讯作者：
C. Zhong;Takehiko Sasaki;Mizuki Tada;Y. Iwasawa
中科院分区：
文献类型：
--
作者：
C. Zhong;Takehiko Sasaki;Mizuki Tada;Y. Iwasawa
制备了含镍离子液体双（1-正丁基-3-甲基咪唑）四氯镍酸盐（[Bmim]2[NiCl 4]）和负载于SiO2表面的含镍离子液体（ImmNi 2 +_IL），并将其应用于芳基氯与芳基硼酸的Suzuki偶联反应.发现催化剂的预处理和三苯基膦的加入对反应有很大的促进作用。[Bmim]2[NiCl 4]和ImmNi 2 +_IL分别用K3 PO 4和NaOtBu处理1 h和30 min，然后再加入底物。确认了ImmNi 2 +_IL的可重复使用性。
Bis(1-n-butyl-3-methyl-imidazolium)tetrachloronickelate ([Bmim]2[NiCl4]), which is a nickel ion-containing ionic liquid, and immobilized nickel ion-containing ionic liquid (ImmNi2+_IL) on silica surface were prepared and applied as new catalysts for Suzuki cross-coupling reactions between aryl chlorides and arylboronic acids. It was found that pretreatment of the catalysts and the addition of triphenylphosphine to the reaction system greatly promoted the reactions. Before the addition of substrates, [Bmim]2[NiCl4] should be treated with K3PO4in dioxane at a refluxing temperature for 1 h, and ImmNi2+_IL should be treated with NaOtBu in dioxane at room temperature for 30 min. An active precursor for the catalytic reactions was found to be a Ni carbene species formed by pretreatment with the bases as characterized by NMR and EXAFS. Reusability was confirmed for ImmNi2+_IL.