20098-48-0Relevant articles and documents
meta-Nitration of Arenes Bearing ortho/para Directing Group(s) Using C?H Borylation
Li, Xuejing,Deng, Xingwang,Coyne, Anthony G.,Srinivasan, Rajavel
supporting information, p. 8018 - 8023 (2019/05/29)
Herein, we report the meta-nitration of arenes bearing ortho/para directing group(s) using the iridium-catalyzed C?H borylation reaction followed by a newly developed copper(II)-catalyzed transformation of the crude aryl pinacol boronate esters into the corresponding nitroarenes in a one-pot fashion. This protocol allows the synthesis of meta-nitrated arenes that are tedious to prepare or require multistep synthesis using the existing methods. The reaction tolerates a wide array of ortho/para-directing groups, such as ?F, ?Cl, ?Br, ?CH3, ?Et, ?iPr ?OCH3, and ?OCF3. It also provides regioselective access to the nitro derivatives of π-electron-deficient heterocycles, such as pyridine and quinoline derivatives. The application of this method is demonstrated in the late-stage modification of complex molecules and also in the gram-scale preparation of an intermediate en route to the FDA-approved drug Nilotinib. Finally, we have shown that the nitro product obtained by this strategy can also be directly converted to the aniline or hindered amine through Baran's amination protocol.
Preparation method of anticoccidial drug Diclazuril
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Paragraph 0021; 0022; 0023, (2018/04/03)
The invention discloses a preparation method of an anticoccidial drug Diclazuril. The method takes 3,4,5-trichloronitrobenzene as a raw material and the 3,4,5-trichloronitrobenzene and 4-chlorobenzylcyanide are subjected to condensation reaction to generate 2,6-dichloro-alpha-(4-chlorobenzyl)-4-nitrophenylacetonitrile; enabling a condensate and hydrazine hydrate to be subjected to reduction to generate 2,6-dichloro-alpha-(4-chlorobenzyl)-4-aminophenylacetonitrile, enabling a reduzate and malonyl ethyl dicarbamate to be subjected to diazo, coupling, cyclization, hydrolysis and decarboxylationone-pot reaction to generate the Diclazuril. The method disclosed by the invention has a simple technology and is easy to operate; the environment protection problem caused by the fact that the odor of thioglycolic acid is great in a decarboxylation process of the Diclazuril is solved; meanwhile, the yield is improved and the total yield of the Diclazuril synthesized by taking 2,6-dichloro p-nitroaniline as the raw material is 43.8 percent, so that the preparation method is suitable for industrial production.
Photochemistry and Photobiological Properties of Dicloran, a Postharvest Fungicide with Photosensitizing Side Effects
Bosca, Francisco,Miranda, Miguel A.,Serrano, Gabriel,Vargas, Franklin
, p. 532 - 537 (2007/10/03)
Photochemical and laser flash photolysis studies on dicloran have shown that this fungicide undergoes photoreactions such as photoreduction of the nitro group and homolytic rupture of the C-NH2 bond. Dramatic changes in the dicloran photoreactivity by the influence of the solvents have been observed. More efficient photodegradation of this fungicide was observed in diethyl ether and chloroform than in methanol or acetonitrile. Photoreduction of the nitro group from the dicloran triplet state seems to be the most important photodegradation pathway in solvents of low polarity. Hydrogen abstraction by the triplet state or the intermediate radicals appears to be in the origin of linoleic acid peroxidations photosensitized by dicloran. The photohemolysis assay has been used, as an in vitro phototoxicity test, to demonstrate the involvement of radical-mediated cellular membrane damage in dicloran photosensitization.