摘要
应用超声波技术在温和条件下以氯丙基三甲氧基硅烷为偶联剂,制得了嫁接过渡金属Zn,Cu,Fe和Co的N,N-双水杨醛缩二乙烯三胺席夫碱配合物[SiO2-M(NNOO)],并与传统加热搅拌法制得的样品的物性和催化性能做了比较.应用IR和UV-Vis谱学技术对其进行了初步表征,结果表明,两种方法制得的嫁接型配合物的红外光谱均呈现出胺基和席夫碱相应基团的特征吸收,配体和配合物红外和紫外光谱之间的差别表明配合物结构的存在.将所制得的样品在苯乙烯选择氧化制苯甲醛反应中进行了催化性能的测试,考察了反应时间和催化剂对苯乙烯转化率和选择性的影响,结果表明苯乙烯转化率均在90%以上,苯甲醛选择性最高可达93.5%,产物选择性与反应时间和催化剂中过渡金属的类型均有关系.
In this paper, transition metal (Zn, Cu, Fe and Co) Schiff base complexes modified SiO2 [SiO2-M(NNOO)] were prepared with 3-chloropropyltrimethoxysilane (CPTMS) as the coupling agents by ultrasonic technique under mild conditions for the first time. The character and catalytic activity of the sample were also compared with those of the sample prepared by traditional methods. The samples were characterized by IR and UV-Vis spectroscopy. The results showed that the characteristic absorption bands of amidocyanogen and Schiff base groups appeared in IR spectroscopy of the samples prepared by the two methods. The presence of complex structure was confirmed by UV-Vis. The catalytic activity of the samples was tested in selective oxidation of styrene to benzaldehyde with H2O2 as oxidant. The influences of reaction time and catalysts on styrene conversion and production selectivities were also studied. The results showed that both high styrene conversion (〉90%) and benzaldehyde selectivity (93.5%) could be obtained. The production selectivities were influenced not only by reaction time but also by the kinds of transition metal in the catalysts.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2006年第24期2479-2485,共7页
Acta Chimica Sinica