Os(VIII)/Ru(III) catalysed oxidation of aspirin drug by a new oxidant, diperiodatoargentate(III) in aqueous alkaline medium: A comparative kinetic study
作者:Chanabasayya V. Hiremath、T.S. Kiran、Sharanappa T. Nandibewoor
DOI:10.1016/j.molcata.2005.12.018
日期:2006.4
The kinetics of Os(VIII) and Ru(III) catalysed oxidation of anti-pyretic drug, aspirin by diperiodatoargentate(III) (DPA) in alkaline medium at 298 K and a constant ionic strength of 0.10 mol dm−3 was studied spectrophotometrically. The oxidation products in both the cases are 1,4-benzoquinone2-carboxylate ion and Ag(I). The stoichiometry is the same in both the catalysed reactions i.e., [aspirin]:[DPA] = 1:2
Os(VIII)和Ru(III)的动力学在298 K和碱性离子强度为0.10 mol dm -3的条件下,在碱性介质中由二硬脂酸双胍(III)(DPA)催化了去热药阿司匹林的氧化。用分光光度法进行了研究。在两种情况下,氧化产物都是1,4-苯醌2-羧酸根离子和Ag(I)。两种催化反应的化学计量均相同,即[阿斯匹林]:[DPA] = 1:2。该反应在Os(VIII)/ Ru(III)和[DPA]中为一级,在[ASP]和[碱]中均小于单元级。已证明在碱性介质中的氧化反应是通过Os(VIII)/ Ru(III)-阿司匹林复合物进行的,该复合物在速率确定步骤中进一步与一分子DPA反应,随后进行其他快速步骤以生成产物。主要产品通过现场测试,IR,NMR和GC-MS鉴定。计算该机理的不同步骤中涉及的反应常数。催化常数(K c还计算了在不同温度下的两种催化反应的)。从log K c相对于1 / T的曲线图