4444-23-9Relevant academic research and scientific papers
Etamsylate and calcium dobesilate impurities, and preparation method and application thereof
-
Paragraph 0083; 0094-0103; 0129-0130, (2020/05/01)
The invention discloses four types of etamsylate and calcium dobesilate impurities, namely a 2,5-dihydroxy-1,4-benzene disulfonic acid compound, a 2,4-dihydroxy-1,5-benzene disulfonic acid compound, a2,5-dihydroxy benzene sulfonate compound and a 2,3-dihydroxy benzene sulfonic acid compound, and a preparation method thereof. The purity of all the prepared compound is 96% or more, and the compounds can be used for the quality control of etamsylate and calcium dobesilate bulk drugs and preparations.
Reductive dehalogenation and dehalogenative sulfonation of phenols and heteroaromatics with sodium sulfite in an aqueous medium
Tomanová, Monika,Jedinák, Luká?,Canka?, Petr
supporting information, p. 2621 - 2628 (2019/06/03)
Prototropic tautomerism was used as a tool for the reductive dehalogenation of (hetero)aryl bromides and iodides, or dehalogenative sulfonation of (hetero)aryl chlorides and fluorides, using sodium sulfite as the sole reagent in an aqueous medium. This protocol does not require a metal or phase transfer catalyst and avoids using organic solvent as the reaction medium. This method is especially suitable for substrates that readily tautomerize (such as 2-or 4-halogenated aminophenols and 4-halogenated resorcinols), for which dehalogenation or sulfonation proceeds under mild reaction conditions (≤60 °C). As sodium sulfite is an inexpensive, safe, and environmentally less hazardous reagent, this method has at least three potential applications: (i) in the deprotection of halogens as protecting groups, using sodium sulfite as a reducing agent; (ii) in the sulfonation of aromatic halides under mild reaction conditions avoiding hazardous and corrosive reagents/solvents; and (iii) in the transformation of toxic halogenated aromatics into less harmful compounds.
Hydroxybenzene disulphonic acid as well as calcium salt and preparation method thereof
-
, (2019/05/08)
A preparation method of hydroxybenzene disulphonic acid comprises steps as follows: hydroquinone and water-containing sulphuric acid are subjected to a reaction to produce a liquid containing hydroxybenzene sulphonic acid, the liquid containing hydroxybenzene sulphonic acid is subjected to a reaction with fuming sulphuric acid, and hydroxybenzene disulphonic acid is produced. A preparation methodof calcium hydroxybenzene disulphonate comprises steps as follows: a liquid containing hydroxybenzene sulphonic acid is produced from hydroquinone and sulphuric acid and is subjected to a reaction with fuming sulphuric acid, a liquid containing hydroxybenzene disulphonic acid is produced and subjected to a reaction with calcium carbonate, and calcium hydroxybenzene disulphonate is produced. The preparation method of hydroxybenzene disulphonic acid, calcium hydroxybenzene disulphonate and the preparation method of calcium hydroxybenzene disulphonate have the advantage that large-scale synthesisof hydroxybenzene disulphonic acid and calcium hydroxybenzene disulphonate is expected to be realized with a certain technology.
An air-stable lithiated cathode material based on a 1,4-benzenedisulfonate backbone for organic Li-ion batteries
Lakraychi,Deunf,Fahsi,Jimenez,Bonnet,Djedaini-Pilard,Bécuwe,Poizot,Dolhem
, p. 19182 - 19189 (2018/10/20)
To meet current market demands as well as emerging environmental concerns there is a need to develop less polluting battery technologies. Organic electrode materials could offer the possibility of preparing electrode materials from naturally more abundant elements and eco-friendly processes coupled with simplified recycling management. However, the potential use of organic electrode materials for energy storage is still challenging and a lot of developments remain to be achieved. For instance, promoting high-energy Li-ion organic batteries inevitably requires the development of lithiated organic electrode materials which are able to be charged (delithiated) at a high enough potential (>3 V vs. Li+/Li0)-a challenging point rarely discussed in the literature. Here, we evaluate tetralithium 2,5-dihydroxy-1,4-benzenedisulfonate as an air-stable lithiated cathode material for the first time and its reversible Li+ electrochemical extraction. Quite interestingly, in comparison with the dicarboxylate counterpart, it was observed that the theoretical two-electron reaction is readily reached with this organic structure and at an average operating potential of 650 mV higher.
Sulfonation and sulfation on reaction of 1,4-dihydroxybenzene and its methyl ethers in concentrated sulfuric acid
Cerfontain, Hans,Koeberg-Telder, Ankie
, p. 583 - 591 (2007/10/02)
The homogeneous reactions of 1,4-dihydroxybenzene (1), its monomethyl (2) and dimethyl ether (3) and 2-3-sulfonic acid in 68-105percent H2SO4 at 25 deg C have been studied and isomer distributions and rate coefficients for the various subsequent sulfonations, as well as the equilibrium data for the sulfation (-OH -OSO3H), are reported.For 2, the ratio of 2- to 3-sulfonation decreases upon increasing the sulfuric acid concentration from 68-98.5percent H2SO4, due to a gradual change-over in the effective sulfonating entity from H3SO4(1+) to H2S2O7.For 1-2-sulfonic acid (1-2-S), 2-2-S and 2-3-S, the ratios of 5- to 6-sulfonation are all ca. 25:75, whereas 3-2-S only yields the 5-sulfonic acid.Demethylation of the sulfonic acids of 2 and 3 in = 98.5percent H2SO4 is of minor importance, but plays a major role in 105,0 percent H2SO4, the eventual products being the bis(hydrogen sulfate)s 10 and 15, the tricyclic bis(sulfate sulfonate anhydride) 11 and the bicyclic hydrogen sulfate 16.Mechanisms for the sulfodemethylation and for the cyclization of the 2-sulfophenyl hydrogen sulfate moiety to the 1,3,2,4-benzodioxadithiin 2,2,4,4-tetraoxide system are proposed.
