绿色离子液体中纳米钯催化剂的制备及其催化Heck-Mizoroki反应性能

摘要

发展了在非卤素绿色离子液体1-丁基-3-甲基咪唑离子液体乳酸盐中制备纳米Pd催化剂的简便化学方法.透射电镜结果表明， Pd纳米粒子高度分散在[Bmim]Lac离子液体中，平均粒径为2.2–3.1 nm. Pd纳米粒子的大小随着体系中[Bmim]Lac与Pd(OAc)2摩尔比减小和温度升高而增大.考察了离子液体稳定纳米Pd催化剂(PdNPs@[Bmim]Lac)催化Heck-Mizoroki反应性能，并对反应条件进行了优化.结果表明，所制备的离子液体稳定的纳米Pd催化剂在优化条件下可高效催化系列卤代芳烃与烯烃的Heck-Mizoroki反应，且可循环使用6次.%A palladium nanoparticle (PdNPs) catalyst was synthesized in halogen‐free anion ionic liquid (1‐buthyl‐3‐methylimidazolium lactate, [Bmim]Lac) by a simple chemical approach. The transmis‐sion electron microscopy analysis confirmed the presence of highly dispersed PdNPs in [Bmim]Lac with small average particle size distribution from 2.2 to 3.1 nm. The size of the PdNPs increases with decreasing molar ratio of [Bmim]Lac to Pd(OAc)2 and increasing temperature. The activity of PdNPs@[Bmim]Lac catalyst was tested by the Heck‐Mizoroki reaction, and the conditions were optimized. The catalyst can efficiently catalyze couplings of various aryl bromides and iodides with different olefins, giving good yields of products under the optimal conditions and be recycled up to six consecutive times.