27701-73-1Relevant academic research and scientific papers
Regioselective Nitration of inactive 4,4-Dibromobiphenyl with Nitrogen Dioxide and Molecular Oxygen over Zeolites: An efficient preparation of 4,4'-Dibromo-2-nitrobiphenyl
Wang, Wei,Peng, Xinhua,Chen, Nan
, p. 72 - 75 (2014/03/21)
In the presence of zeolites, 4,4'-dibromobiphenyl could be region-selectively nitrated by the action of nitrogen dioxide and molecular oxygen. The ratio of 4,4'-dibromo-2-nitrobiphenyl to 4,4'-dibromo-3- nitrobiphenyl could reach 14 in a high yield of 90%. Zeolites could be easily regenerated by heating and reused four times to give the results similar to those obtained with fresh catalyst. Compared with the classic nitration method, no nitric acid and sulfuric acid were used, which suggested that the method was an environmentally economic process.
Regioselective preparation of 4-nitro-o-xylene using nitrogen dioxide/molecular oxygen over zeolite catalysts. remarkable enhancement of para-selectivity
Liu, Hongtao,Ji, Cheng,Dong, Xiongzi,Peng, Xinhua,Shi, Chunjie
supporting information, p. 817 - 819 (2014/06/23)
In the presence of molecular oxygen and zeolite H-β with Si/Al 2 = 500, o-xylene reacted regioselectively with liquid nitrogen dioxide at 35 °C to yield mononitro-o-xylenes as the main product, where the 4-nitro-o-xylene isomer predominated up to 89% and the 4-nitro-/3-nitro-o- xylene isomer ratio improved to 7.8. The process is eco-friendly, less expensive, and the zeolite could be easily regenerated by a simple workup to afford results similar to those obtained with the fresh catalyst.
