β-环糊精-Cu(Ⅱ)配合物催化氧化邻苯二酚及其反应动力学  

Oxidation of catechol catalyzed by β-cyclodextrin-Cu(Ⅱ) complexes and its reaction kinetics

作　　者：王秉[1] 胡智文[1] 郑海玲[1] 杨海亮[1] 黄小芳[1] 张殿波[1] 万军民[1] 

机构地区：[1]浙江理工大学先进纺织材料与制备技术教育部重点实验室,浙江杭州310018

出　　处：《化工学报》2009年第6期1459-1465,共7页CIESC Journal

基　　金：国家自然科学基金项目(20206019);浙江省自然科学基金项目(M503216)~~

摘　　要：以β-环糊精(β-CD)作为骨架,经磺酰化反应、卤代反应和与L-组氨酸的亲核取代反应,得到了两种β-环糊精-组氨酸衍生物配体,再将配体与Cu(Ⅱ)配位,合成了具有多酚氧化酶催化活性的β-环糊精-Cu(Ⅱ)配合物。采用元素分析、傅里叶变换红外光谱、核磁共振波谱和原子吸收光谱等方法对配体和配合物的结构进行了表征。以O2为氧化剂,用分光光度法测定了它们催化邻苯二酚氧化反应的性能,并考察了反应温度、pH值等因素对催化反应速率的影响。结果表明:β-环糊精-Cu(Ⅱ)配合物具有良好的催化性能;C-2位修饰得到的环糊精类金属衍生物因为活性基团与反应中心之间相对位置适宜,表现出较大的加速效果;反应动力学表明组胺基配位Cu(Ⅱ)、β-CD疏水空腔和碱催化作用是反应加速的3个因素。Two kinds of β-cyclodextrin （β-CD） derivatives mono-6-（N-histamino）-6-deoxy-β- cyclodextrin （6-His-β-CD） and mono-2-（N-histamino）-2-deoxy-β-cyclodextrin （2-His-13-CD） were prepared by reacting β-CD with p-toluene sulfonyl chloride, displacement the monotosylate with iodide, and finally the reaction of cyclodextrin iodide with nucleophile L-histidine. From these derivatives, the β-CD-Cu（ Ⅱ ） complexes （Cu（ Ⅱ ）/6-His-β-CD, Cu（ Ⅱ ）/2-His-β-CD） with polyphenol oxidase （PPO） activity were synthesized. The derivatives and the complexes were characterized with elemental analysis, Fouriertransform infrared spectroscopy, nuclear magnetic resonance spectroscopy and atomic absorption spectrometry. The complexes were used as catalysts for the oxidation of catechol using O2 as the oxidant, which was monitored by UV-Vis spectrophotometer. The effects of temperature and pH value on the reaction were also studied. The results indicated that the PPO mimics exhibited high catalytic activities. Cu （ Ⅱ ）/2-His-β-CD showed higher PPO activity than Cu（ Ⅱ ）/6-His-β-CD. The kinetic studies showed that all three factors, the hydrophobic environment provided by β-CD, the Cu（ Ⅱ ） bound to the histamine and the base catalysis contributed to the PPO activity.

关 键 词：Β-环糊精 多酚氧化酶 催化 邻苯二酚 反应动力学 

分 类 号：TQ032[化学工程] O643[理学—物理化学]