Conversion of anilines into azobenzenes in acetic acid with perborate and Mo(VI): correlation of reactivities
作者:C. Karunakaran、R. Venkataramanan
DOI:10.1007/s11696-018-0599-z
日期:2019.2
azobenzenes in good yield from commercially available anilines using sodium perborate (SPB) and catalytic amount of Na2MoO4 under mild conditions. Glacial acetic acid is the solvent of choice and the aniline to azobenzene conversion is zero, first and first orders with respect to SPB, Na2MoO4 and aniline, respectively. Based on the kinetic orders, UV–visible spectra and cyclic voltammograms, the conversion
偶氮苯被广泛用于纺织品和皮革的染色,通过调节环中的取代基,可以获得鲜艳的色彩。在这里,我们报道了在温和条件下,使用过硼酸钠(SPB)和催化量的Na 2 MoO 4由市售苯胺以高收率制备大量的偶氮苯。冰醋酸是首选的溶剂,苯胺到偶氮苯的转化率是零,相对于SPB,Na 2 MoO 4来说,是一阶和一阶和苯胺。根据动力学级数,紫外可见光谱和循环伏安图,提出了转化机理。在20–50°C时约50个苯胺的反应速率及其能量和活化熵分别符合等动力学或Exner关系和补偿效应。然而,由迄今为止采用的方法推导的反应速率不能符合哈米特相关性。通过改进的计算获得的分子苯胺的特定反应速率符合哈米特关系。因此,这项工作提出了一种方便,廉价,无害的制备大量偶氮苯的方法,