Mechanistic studies of oxidation of maltose and lactose by [H2OBr]+ in presence of chloro-complex of Rh(III) as homogeneous catalyst
作者:Ashok Kumar Singh、Reena Singh、Jaya Srivastava、Shahla Rahmani、Shalini Srivastava
DOI:10.1016/j.jorganchem.2007.06.035
日期:2007.9
both the redox systems. The rate of oxidation is unaffected by the change in ionic strength (μ) of the medium. The main oxidation products of the reactions were identified as formic acid and arabinonic acid in the case of maltose and formic acid, arabinonic acid and lyxonic acid in the case of lactose. A common mechanism for the oxidation of both maltose and lactose, showing the formation of most reactive
在均匀的Rh(III)的动力学研究还原糖的催化的氧化作用,即,麦芽糖和乳糖,由Ñ在高氯酸的存在下-bromoacetamide(NBA)已在40℃下用乙酸汞作为溴作了-离子清除剂。两种还原糖氧化的结果表明,低浓度下反应对NBA呈一阶依赖性,高浓度下反应向零阶转变。观察到[Rh(III)]中的一级动力学和[还原糖]中的零级动力学。[氯的积极作用-在这两个麦芽糖和乳糖的氧化观察到]。在[H +在麦芽糖和乳糖的氧化中。在两个氧化还原体系中,均观察到反应速率的增加和[Hg(OAc)2 ]和[NHA]的降低。氧化速率不受介质离子强度(μ)的影响。在麦芽糖的情况下,该反应的主要氧化产物被鉴定为甲酸和阿拉伯糖酸;在乳糖的情况下,被鉴定为甲酸,阿拉伯糖酸和lyxonic酸。麦芽糖和乳糖氧化的常见机制,表明形成了最具反应性的活化复合物[RhCl 4(H 3 O)H 2 OBr] +和不反应的络合物[RhCl