Applicability of aluminum amalgam to the reduction of arylnitro groups

[摘要] An array of arylnitro compounds with various functionality were treated with freshly-prepared aluminum amalgam in THE/water solution and resulted in the corresponding arylamines. The Al(Hg)-mediated reductions are relatively rapid with consumption of the amalgam and disappearance of starting material occurring over 20-30 min. The workup of the reductions involves only removal of the insoluble by-products by filtration followed by concentration. Only in some cases is chromatography required to secure the pure product. The desired arylamines are furnished in quantities of 25-100 mg, which in some cases, could be taken on to the next reaction without further purification. Reductions of 4-nitrobenzyl derivatives of carbohydrates or nucleosides were selective in affording the corresponding 4-aminobenzyl products. To show applicability in click chemistry, selected aminobenzyl products are directly azidated to yield products that were then used in click reactions to afford the corresponding 1,2,3-triazoles. (C) 2020 Elsevier Ltd. All rights reserved.

[发布日期] 2020-11-19

[关键词] Aluminum amalgam;Arylnitro groups;Azides;Click chemistry;Reduction