2835-05-4Relevant academic research and scientific papers
Cornforth and Corey-Suggs reagents as efficient catalysts for sulfonation of aromatic and heteroaromatic compounds using NaHSO3 under solvent free and microwave conditions
Fatima, Touheeth,Duguta, Govardhan,Purugula, Venkanna,Yelike, Hemanth Sriram,Kamatala, Chinna Rajanna
, p. 1001 - 1006 (2020/07/27)
Cornforth and Corey-Suggs reagents Pyridinium Dichromate (PDC) and Pyridinium Chlorochromate (PCC) were explored as efficient catalysts for sulfonation of aromatic and heteroaromatic compounds using NaHSO3 in aqueous acetonitrile medium at room temperature within 1–4 h, while microwave assisted reactions took place within 1–4 min under solvent-free conditions. These observations indicate significant rate accelerations in microwave assisted reactions. which were explained due to the bulk activation of molecules induced by insitu generated high temperatures and pressures when microwaves are transmitted through reaction medium.
Synthesis method of 2-amino-5-methoxybenzene sulfonic acid
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, (2017/01/02)
The invention discloses a synthesis method of 2-amino-5-methoxybenzene sulfonic acid, and belongs to the technical field of organic chemosynthesis. According to the method, firstly, 2H2SO4 and sodium nitrate are added into phenol to generate p-nitrophenol; then, zinc powder and hydrochloric acid are added; p-aminophenol is further generated; then, concentrated sulfuric acid and an Aladdin reagent are dropwise added into the aminophenol; 2-amino-5-methoxybenzene sulfonic acid is obtained after the reaction; then, a sodium hydroxide solution is added to generate 2-amino-5-sodium epoxide phenol sodium; finally, a CH3I solution is added into the 2-amino-5-sodium epoxide phenol sodium; after the 2-amino-5-sodium epoxide phenol sodium is generated, a H2SO4 solution is added at high temperature; the 2-amino-5-methoxybenzene sulfonic acid is generated. Examples prove that the method provided by the invention has the advantages that the operation is simple; the implementation is easy; no any toxicity exists; in addition, the synthesized product can be easily, automatically and biologically degraded; the synthesis yield reaches higher than 82 percent.
Development of an efficient ruthenium catalyzed synthetic process and mechanism for the facile conversion of benzothiazoles to orthanilic acids
Jagadeesh,Karthikeyan,Nithya,Sandhya, Y. Sree,Reddy, S. Sudhaker,Reddy, P. Pradeep Kumar,Kumar, M. Vinod,Charan, K.T. Prabhu,Narender,Bhagat
experimental part, p. 99 - 107 (2010/12/18)
Ruthenium-Schiff base complex catalyzed efficient protocol has been developed for the synthesis of orthanilic acids from benzothiazoles in good to excellent yields using N-haloamines. Hexa-coordinated ruthenium complex with Schiff base and triphenylphosphine ligands has been prepared and its catalytic function was invented for the synthesis of orthanilic acids. The synthetic process utilizes our efficient method for the selective and preferential oxidation of thiazole ring of benzothiazoles using N-haloamines without effecting phenyl ring. The detailed catalytic, mechanistic and kinetic investigations have been made for the synthetic reactions. Solvent isotope studies have been made in H2O-D2O and the reactions were carried out at different temperatures. Under the identical set of conditions, the kinetics of catalyzed reactions has been compared with uncatalyzed reactions and found that the catalyzed reactions are 9-11 folds faster. The catalytic constants (KC) have been calculated for each N-haloamine at different temperatures and the values of activation parameters with respect to the catalyst have been evaluated. Spectroscopic evidence for the formation of 1:1 complex between N-haloamine and ruthenium has been obtained. The observed results have been explained by a plausible mechanism and the related rate law has been deduced.
Laccase-mediated synthesis of novel substituted phenoxazine chromophores featuring tuneable water solubility
Bruyneel, Frederic,Payen, Olivier,Rescigno, Antonio,Tinant, Bernard,Marchand-Brvnaert, Jacaueline
, p. 8283 - 8295 (2011/03/20)
Laccases are members of the blue copper oxidases family found in nature. They commonly oxidise a wide range of phenol and aniline derivatives, which in turn are involved in oxidative coupling reactions. Yet, laccases remain rarely described as biocatalysts in organic synthesis. This paper describes the chemical preparation of original sulfonated aminophenol substrates and their enzyme-mediated dimerisation into phenoxazine chromophores that feature tuneable water solubility as a function of the sulfonyl substituent. The scope and limitations of the bio-catalysed synthetic process are outlined. Kinetic data were collected to evaluate the influence of physicochemical parameters. The structure of the novel phenoxazine dyes ("head-to-head" or "head-to-tail" dimer) was assessed by NMR spectroscopic analysis. Two crystalline compounds were analysed by X-ray diffraction. Such lac-case-mediated synthesis (a green chemistry process) was proven to be more efficient than the chemical oxidation of o-aminophenols with silver oxide.
Fiber reactive anthraquinone dyes
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, (2008/06/13)
The invention is that of a water soluble fiber reactive anthraquinone blue dyes. These dyes may be used to dye and print textiles and other substrates containing hydroxy and or groups in brilliant blue colors. The dyes of the invention are free of heavy metals.
