CAJ | 학술논문

采用有机金属Pd_2(dba) _3(dba为二亚苄基丙酮)还原分解法制得均匀分布的Pd纳米颗粒(粒径为3～6nm)混合液,并用活性炭直接吸附得到了组合型Pd/C纳米催化剂.采用透射电子显微镜、X射线光电子能谱和X射线衍射等手段测定了催化剂表面Pd颗粒大小分布、晶型和化学态等.将该催化剂用于Suzuki碳-碳偶联反应,其催化活性比浸渍法制备的Pd/C催化剂高2倍以上.以溴代芳烃为底物时,在80℃下0.5h后偶联产物收率可达98%以上.以邻氯硝基苯为底物时,在110°C下1 h后偶联产物收率可达64%:延长反应时间,产物收率可达90%以上.
채용유궤금속Pd_2(dba) _3(dba위이아변기병동)환원분해법제득균균분포적Pd납미과립(립경위3～6nm)혼합액,병용활성탄직접흡부득도료조합형Pd/C납미최화제.채용투사전자현미경、X사선광전자능보화X사선연사등수단측정료최화제표면Pd과립대소분포、정형화화학태등.장해최화제용우Suzuki탄-탄우련반응,기최화활성비침지법제비적Pd/C최화제고2배이상.이추대방경위저물시,재80℃하0.5h후우련산물수솔가체98%이상.이린록초기분위저물시,재110°C하1 h후우련산물수솔가체64%:연장반응시간,산물수솔가체90%이상.
The Pd nanoparticles with diameters of 3-6 nm were obtained by the decomposition of Pd_2(dba) _3 (dba = dibenzalacetone). They were captured by activated carbon directly to prepare the assembled Pd/C catalyst. Transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction were used to characterize the size, distribution, and electronic state of Pd nanoparticles. This assembled catalyst showed extraordinary properties in Suzuki coupling reaction, which was over twice than the Pd/C catalyst prepared by the impregna-tion method. Under the conditions of 80 ℃ and 0.5 h, the catalyst can catalyze Suzuki reactions of aryl bromide with a coupling product yield of 98%. The assembled Pd/C catalyst can also catalyze the reaction of o-chloronitrobenzene with a yield of 64% in 1 h when the reac-tion temperature was 110 ℃, and the yield can be higher than 90% with extending the reaction time.