88-21-1Relevant articles and documents
Bimolecular proximity of a ruthenium complex and methylene blue within an anionic porous coordination cage for enhancing photocatalytic activity
Fang, Yu,Xiao, Zhifeng,Kirchon, Angelo,Li, Jialuo,Jin, Fangying,Togo, Tatsuo,Zhang, Liangliang,Zhu, Chengfeng,Zhou, Hong-Cai
, p. 3529 - 3534 (2019/03/28)
The charge repulsion between a catalyst and substrate will significantly reduce the contact occurring between them, resulting in low reactivity. Herein, we report an anionic porous coordination cage that is capable of encapsulating both a cationic catalyst and cationic substrate in its cavity at the same time. After encapsulating the [Ru(bpy)3]2+Cl2 (bpy = bipyridine) catalyst, the cage/catalyst composite serves as an active heterogeneous catalyst for the photo-degradation of methylene blue (MB). The highly negatively charged cavity of PCC-2 allows for the sequential encapsulation of the cationic methylene blue substrate and the Ru catalyst, which in turn significantly shortens the distance between them, yielding an increased possibility of MB degradation. Moreover, the encapsulated Ru catalyst dramatically outperformed its homogeneous counterpart in terms of overall degradation performance and recyclability.
Orthanilic acid synthesizing method
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Paragraph 0053; 0056; 0067; 0077; 0087; 0098; 0109, (2018/03/25)
The invention discloses an orthanilic acid synthesizing method. The method includes steps: step one, taking water as a reaction medium, mixing ortho-nitrochlorobenzene and sodium disulfide solution, and stirring at 60-90 DEG C until reaction is finished, so that bis(dinitrophenyl)disulfide is obtained; step two, taking water as a reaction medium, adding the bis(dinitrophenyl)disulfide while addingan oxidant into a reaction system, stirring at 60-90 DEG C until reaction is finished, so that aqueous solution of o-nitrobenzenesulphonic acid is obtained; step three, taking water as a reaction medium and o-nitrobenzenesulphonic acid as a reaction substrate, adding or not adding auxiliary agents, adding catalysts under conditions of 90-120 DEG C and 0.8-2.0MPa, stirring until reaction is finished, and acidizing to obtain orthanilic acid. The orthanilic acid yield of the method reaches 90% or above and increased by 20% or above as compared with that of an old process, product purity is higher than 99.5%, and great crystal form and freeness of metal ion residues are realized. The method has advantages of high economic benefits, environmental friendliness and the like.
Design and mechanism of iron catalyzed carbon-carbon bond cleavage and N-oxidation processes of hazardous dyes for selective synthesis of nitroarenes and aminoarenecarboxylic acids
Jagadeesh, Rajenahally V.,Kiran,Bhagat, Pundlik R.,Kumar, S. Senthil,Nithya,Khan, F. Nawaz,Sivakumar
experimental part, p. 92 - 104 (2011/05/05)
An efficient iron catalyzed oxidative degradation process has been developed for selective conversion of environmentally hazardous azo and indigo dyes into nitroarenes and aminoarenecarboxylic acids (anthranilic acids) respectively, using polymer supported tribromide reagent at an alkaline pH. The in situ generated and the isolated (defined) chloro-iron(II)-terpyridine- pyridine carboxylate [Fe(tpy)(pic)Cl] catalyst system has been developed and its catalytic function was invented for the degradation process. The different nitrogenous and oxygen ligands have been screened out for the development of best catalyst system, and eventually we explored pyridine 2-carboxylic acid and terpyridine ligands together, were found to be the best. Notably, the in situ generated and the defined catalyst systems have found to be more effective with similar catalytic activities towards the oxidative degradation of both the dyes. As a result, the whole oxidative degradation process has been carried out with Fe(tpy)(pic)Cl catalyst system and the general process utilizes the efficient catalytic method for the selective oxidation of -NN- and -CC- bonds of azo and indigo dyes respectively. The detailed catalysis, mechanistic and kinetic investigations have been made for the reactions. Interestingly, both the dyes proceed with a common oxidative degradation mechanism under identical kinetic patters. A common oxidative degradation mechanism which operates in both the dyes has been proposed and an identical related kinetic model was designed. The main interesting aspect of the present work pertains to the catalytic conversion of environmentally hazardous compounds into useful molecules; such are anthranilic acids and nitrobenzenes. Other special aspect related to catalytic activity of iron and potentially, iron catalyst accelerates the reaction rates with 15-20-fold faster. The reactions were also carried out with different polymer supported trihalide and inter-halide reagents. Notably, trichloride and inter-halide regents were found to be more reactive. The catalytic method developed for the degradation process was found to be very efficient and the involvement of cost-effective reagents makes the reaction simple, and can be conveniently scalable to industrial/technological operations with suitable modifications.