对硝基甲苯在多硫化钠溶液中氧化还原机理的质谱研究

采用高分辨质谱仪跟踪监测对硝基甲苯在多硫化钠存在下于乙醇-碱性水溶液中生成对氨基苯甲醛过程中反应中间体的变化及转变规律.结果显示,在80℃时反应进行到120min之内,有数种分子量较大的缩合中间体生成,表明对氨基苯甲醛可能是经类席夫碱的多聚体水解生成的.同时,对席夫碱多聚体的形成提出了与文献不同的机理.

A Mass Spectroscopic Investigation to Redox Mechanism of p-Nitrotoluene in Sodium Polysulfide Solution

The reaction of p-nitrotoluene in the ethanol/sodium polysulfide solution resulting in {p-aminobenzaldehyde} has been applied to industry. However the reaction mechanism is not accepted commonly since the accordant conclusion among the proposed mechanisms was not reached due to lacking of the verification mutually. In this paper, we monitored the reaction intermediates and their transition regularity by high resolution mass spectra. The results show that the condensation compounds emerged during the reaction at 80 ℃ with the reaction starting up to 120 min, strongly supporting the condensation and oxidation mechanisms proposed by Shchukina and Chen, respectively, that is, p-aminobenzaldehyde is derived from the hydrolysis of poly Schiff base. Meanwhile, we propose the possibility of formation process of poly Schiff base, which is different from that reported in literatures.