616-79-5Relevant articles and documents
The cleavage of heterocyclic compounds in organic synthesis II [1] use of 5-nitroisatine for synthesis of various nitrogenous heterocycles
Hlavac, Jan,Soural, Miroslav,Hradil, Pavel,Frysova, Iveta,Slouka, Jan
, p. 633 - 636 (2004)
The reactions of 5-nitroisatine were studied with nucleophiles like heterocyclic amines and alkaline hydroxide. With the use of alkaline hydroxide it was converted into 2-amino-5-nitrophenylglyoxylic acid 2, with piperidine, morpholine and carbethoxypiperazine to its amides 4a-4c or by oxidation to 5-nitroanthranilic acid 7. This acid was used for synthesis of 3-hydroxy-6-nitro-2-phenyl-1H-quinolin-4-one 10. Semicarbazone of 5-nitroisatine 11 was converted to 5-(2-amino-5-nitrophenyl)-2,3,4,5-tetrahydro-1,2,4- triazine-3,5-dione 12. Cyclocondensation of this compound to afford 8-nitro-2,3-dihydro-5H-[1,2,4]triazino-[5,6-b]indol-3-one 13 was unsuccessful.
Isoxazole formamido-4 (3H)-quinazolinone derivative as well as synthesis method and application thereof
-
, (2021/06/06)
The invention relates to a 6-(isoxazolyl-3-formamido)-4 (3H)-quinazolinone derivative as well as a synthesis method and application thereof, belongs to the technical field of medicines, and relates to a general formula (I) in which R1, R2 and R3 are different substituent groups. The invention discloses structures and synthesis methods of the compounds, inhibitory activity of acetylcholin esterase and inhibitory activity of protein tyrosine phosphatase, and the compounds can be further developed into drugs for treating Alzheimer's disease.
A green and recyclable ligand-free copper (I) catalysis system for amination of halonitrobenzenes in aqueous ammonia solution
Li, Yan,Shi, Ruhui,Lin, Weiwei,Cheng, Haiyang,Zhang, Chao,Arai, Masahiko,Zhao, Fengyu
, (2019/06/18)
The amination of halonitrobenzenes is an important reaction to produce the corresponding nitroanilines. Direct amination of p-chloronitrobenzene (p-CNB) to p-nitroaniline (p-NAN) with aqueous NH3 solution was investigated over various transition metal salts in the absence of ligand, inorganic base and organic solvent. It was found that CuI is the most effective catalyst with respect to p-CNB conversion, p-NAN selectivity (≈ 100%) and the post-reaction separation and recycling. A high p-NAN yield of 97% could be obtained at 200 °C in 6.5 h with molar ratios of NH3/p-CNB and CuI/p-CNB of 21 and 0.1, respectively. A possible reaction mechanism was proposed, in which NH3 was not only a substrate but also a ligand to coordinate with CuI and formed a water-soluble Cu complex, and then it started the catalytic cycle. The influence of reaction variables such as NH3 concentration, CuI concentration, temperature and time on the p-CNB conversion and the p-NAN selectivity was examined. At room temperature the desired product of p-NAN is insoluble in water but the Cu complex catalyst is water-soluble and so the aqueous phase including the catalyst and NH3 can be easily separated and reused for the subsequent reaction runs. The green and sustainable system is effective for the conversion of diverse halonitrobenzenes to nitroanilines.
Nickel-Catalyzed Regioselective C–H Bond Mono- and Bis-Nitration of Aryloxazolines with tert-Butyl Nitrite as Nitro Source
Wan, Li,Qiao, Kai,Yuan, Xin,Zheng, Ming-Wei,Fan, Bing-Bing,Di, Zhe Chen,Zhang, Dong,Fang, Zheng,Guo, Kai
, p. 2596 - 2604 (2017/08/16)
An efficient and regioselective nickel-catalyzed remote C–H nitration of 2-aryloxazoline amides using the non-corrosive tert-butyl nitrite (TBN) as nitro source has been developed. The protocol makes use of inexpensive nickel salts as catalysts and delivers the corresponding products in excellent yields. Notably, bis-nitration products were obtained by simply increasing the amount of tert-butyl nitrite. This reaction proceeds in air and features excellent functional group compatibility, broad substrate scope and is suitable for gram-scale synthesis. (Figure presented.).