Abstract

A green, facile, fast, and high throughput reusable catalytic reduction process was developed for the large-scale reduction of tris(p-nitrophenyl)amine to its corresponding amino-compound, tris(p-aminophenyl)amine (TAPA). The homogenous AgNPs and NaBH₄ were used as the H-transfer catalyst and the H-donor compound, respectively. The successful reduction of TNPA was investigated by FT–IR, EDX, and XRD analysis, and its optical properties were checked by the UV–Visible and FL spectroscopies. Factors affecting the reduction yield including, temperature, reaction time, mmol of NaBH₄, and catalyst volume, were optimized. Although the AgNPs are homogenous, both TNPA and TAPA are insoluble in water (AgNPs), hence the reduction process is heterogeneous. The importance of the heterogeneous reduction of TNPA was investigated, indicated that the reduction yield reached its maximum value when TNPA heterogeneously reduced on the surface of AgNPs. The reduction yield at optimal conditions was calculated at about 98.0% for the first and 72.0% after the 6^th operational cycle, respectively. The mechanism of the reduction process was also established, indicated that the process works through a possible Langmuir–Hinshelwood mechanism. The easy recovery and excellent reusability of homogenous AgNPs along with high reaction yield reveal the power of the proposed method for the reduction of nitro-compounds.

Graphic abstract

Synopsis A high throughput reusable catalytic reduction process has developed for the reduction of tris(p-nitrophenyl)amine to its corresponding amino-compound, tris(p-aminophenyl)amine (TAPA) using the homogenous AgNPs the H-transfer. As a significant advantage, the developed method works through a green chemistry approach.

中文翻译：

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在室温下用均相AgNP作为H转移催化剂高通量绿色还原三（对硝基苯基）胺

摘要

为了将三（对硝基苯基）胺大规模还原为相应的氨基化合物三（对氨基苯基）胺（TAPA），开发了一种绿色，简便，快速且高通量的可重复使用的催化还原工艺。均质的AgNP和NaBH ₄分别用作H-转移催化剂和H-供体化合物。通过FT-IR，EDX和XRD分析研究了TNPA的成功还原，并通过UV-Visible和FL光谱学检查了其光学性质。影响还原产率的因素包括温度，反应时间，NaBH _4的mmol和催化剂体积进行了优化。尽管AgNPs是同质的，但TNPA和TAPA都不溶于水（AgNPs），因此还原过程是异质的。TNPA异质还原的重要性进行了调查，表明当TNPA在AgNPs表面异质还原时，还原产率达到最大值。在最佳条件下，第一次还原的产率约为98.0％，第六^次还原的产率为72.0％操作周期。还建立了还原过程的机制，表明该过程通过可能的Langmuir-Hinshelwood机制起作用。均一的AgNPs易于回收，出色的可重复使用性以及较高的反应产率，揭示了所提出的还原硝基化合物的方法的强大功能。

图形摘要

概要已开发出一种高通量可重复使用的催化还原方法，该方法使用H-转移均质AgNP将三（对硝基苯基）胺还原成其相应的氨基化合物三（对氨基苯基）胺（TAPA）。作为一个显着的优势，开发的方法通过绿色化学方法起作用。