C:Corrosive;61380-66-3Relevant articles and documents
Selective Late-Stage Sulfonyl Chloride Formation from Sulfonamides Enabled by Pyry-BF4
Gómez-Palomino, Alejandro,Cornella, Josep
supporting information, p. 18235 - 18239 (2019/11/13)
Reported here is a simple and practical functionalization of primary sulfonamides, by means of a pyrylium salt (Pyry-BF4), with nucleophiles. This simple reagent activates the poorly nucleophilic NH2 group in a sulfonamide, enabling the formation of one of the best electrophiles in organic synthesis: a sulfonyl chloride. Because of the variety of primary sulfonamides in pharmaceutical contexts, special attention has been focused on the direct conversion of densely functionalized primary sulfonamides by a late-stage formation of the corresponding sulfonyl chloride. A variety of nucleophiles could be engaged in this transformation, thus permitting the synthesis of complex sulfonamides, sulfonates, sulfides, sulfonyl fluorides, and sulfonic acids. The mild reaction conditions and the high selectivity of Pyry-BF4 towards NH2 groups permit the formation of sulfonyl chlorides in a late-stage fashion, tolerating a preponderance of sensitive functionalities.
Voriconazole resolving agent (R)-10 - camphor sulfonic acid recovery method
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Paragraph 0028-0029; 0034-0035; 0037-0046, (2018/07/30)
The invention discloses a Voriconazole resolving agent (R)- 10 - camphorsulfonic acid recovery method, comprises the following steps: (1) alkali treatment: the Voriconazole is soluble in methylene chloride and water camphor sulfonate in the mixed solution of, adding alkali treatment of weak base aqueous solution, to be delaminated separation, keeps the water level for use; (2) the acidification process: in step (1) by adding a strong acid in the aqueous layer of the acidification process, then the concentration and evaporation drying to get the solid; the resulting solid under the heating condition is dissolved in the organic solvent, filtering, remain filtrate for use; (3) crystallization processing: the cyclohexane are added to step (2) in the filtrate obtained by, cooling crystallization, crystallization carried out upon completion of filtering, to obtain the (R)- 10 - camphorsulfonic acid. Voriconazole resolving agent (R)- 10 - camphorsulfonic acid recovery method has a simple separation, separation product has high optical purity, economic, environmental protection and the like.
Method for recycling camphorsulfonic acid
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Paragraph 0021; 0022, (2018/01/14)
The invention discloses a method for recycling camphorsulfonic acid. The method is used for aqueous solution with camphorsulfonic acid salt generated in the production process of ephedrine. The method includes the steps: performing acidic precipitation; performing filtration to remove inorganic salt to obtain camphorsulfonic acid aqueous solution; concentrating the camphorsulfonic acid aqueous solution, adding sulfuric acid to crystallize; performing filtering and washing to obtain the camphorsulfonic acid. The method is simple and stable in process, high in optical purity, low in energy consumption and production cost and suitable for large-scale industrial production, retrieving rate is 90% or more, and waste gas, waste water and solid waste are less and easily controlled.
Enantiomeric separations of chiral sulfonic and phosphoric acids with barium-doped cyclofructan selectors via an ion interaction mechanism
Smuts, Jonathan P.,Hao, Xin-Qi,Han, Zhaobin,Parpia, Curran,Krische, Michael J.,Armstrong, Daniel W.
, p. 1282 - 1290 (2014/02/14)
New cyclofructan-6 (CF6)-based chiral stationary phases (CSPs) bind barium cations. As a result, the barium-complexed CSPs exhibit enantioselectivity toward 16 chiral phosphoric and sulfonic acids in the polar organic mode (e.g., methanol or ethanol mobile phase containing a barium salt additive). Retention is predominantly governed by a strong ionic interaction between the analyte and the complexed barium cation as well as hydrogen bonding with the cyclofructan macrocycle. The log k versus log [X], where [X] = the concentration of the barium counteranion, plots for LARIHC-CF6-P were linear with negative slopes demonstrating typical anion exchange behavior. The nature of the barium counteranion also was investigated (acetate, methanesulfonate, trifluoroacetate, and perchlorate), and the apparent elution strength was found to be acetate > methanesulfonate > trifluoroacetate > perchlorate. A theory based upon a double layer model was proposed wherein kosmotropic anions are selectively adsorbed to the cyclofructan macrocycle and attenuate the effect of the barium cation. van't Hoff studies for two analytes were conducted on the LARIHC-CF6-P for three of the barium salts (acetate, trifluoroacetate, and perchlorate), and the thermodynamic parameters governing retention and enantioselectivity are discussed. Interestingly, for the entropically driven separations, enantiomeric selectivity can increase at higher temperatures, even with decreasing retention.
Influence of norbornanone substituents on both the Wagner-Meerwein skeletal rearrangements under sulfonation conditions and the diastereoselectivity of the corresponding N,N′-bis-fumaroyl sultams in uncatalyzed Diels-Alder cycloadditions to cyclopenta-1,3-diene
Pia?tek, Anna,Chapuis, Christian
, p. 4247 - 4249 (2013/07/26)
The Wagner-Meerwein domino rearrangement of norbornanone skeletons, under sulfonation conditions, is strongly influenced by the absence of a gem-dimethyl moiety at C(7). As a result, sulfonation at C(10) is less efficient due to a divergent pathway in the intermediate double bond formation and/or isomerization. Furthermore, the absence of such a gem-dimethyl moiety in the corresponding norbornane[10,2]sultam derivatives, sterically influences the orientation of the SO(1) and SO(2) substituents, hence on the π-facial steric shielding of the thermodynamically more stable anti-s-cis N-alkenoyl dienophiles. As a consequence, their diastereoselective [4+2] cycloadditions to cyclopenta-1,3-diene, under nonchelating conditions, are not as efficient due to a less pseudo axial SO(1) and the consequent loss of pseudo C 2-symmetry.
Identification of small molecule sulfonic acids as ecto-5'-nucleotidase inhibitors
Raza, Rabia,Saeed, Aamer,Lecka, Joanna,Sévigny, Jean,Iqbal, Jamshed
, p. 1133 - 1139 (2013/01/15)
Ecto-5'-Nucleotidase inhibitors have great potential as anti-tumor agents. We have investigated biochemical properties of human and rat ecto-5'-Nucleotidases and characterized 19 small molecule sulfonic acid derivatives as potential inhibitors of ecto-5'-Nucleotidases. We identified 11 potent inhibitors of human and rat ecto-5'-Nucleotidases and checked their selectivity. Compound 10 (Sodium 2,4-dinitrobenzenesulfonate) with Ki value of 0.66 μM and 19 (N-(4- sulfamoylphenylcarbamothioyl) pivalamide) with Ki value of 0.78 μM were identified as the most potent inhibitors for human and rat ecto-5'-Nucleotidase, respectively. The present compounds have low molecular weights, water solubility and equal potency as compared to the reported inhibitors.
Reactive Extraction of Free Organic Acids from the Ammonium Salts Thereof
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Page/Page column 12, (2010/08/22)
The invention relates to a process for converting ammonium salts of organic acids to the particular free organic acid, wherein an aqueous solution of the ammonium salt is contacted with an organic extractant and the salt is dissociated at temperatures and pressures at which the aqueous solution and the extractant are in the liquid state, and a stripping medium or entraining gas is introduced in order to remove NH3 from the aqueous solution and transfer at least a portion of the free organic acid formed to the organic extractant. The invention described here thus provides an improved process for releasing an organic acid, preferably a carboxylic, sulphonic or phosphonic acid, especially an alpha-hydroxycarboxylic acid or beta-hydroxycarboxylic acid, from the ammonium salt thereof by release and removal of ammonia and simultaneous extraction of the acid released with a suitable extractant from the aqueous phase. This process corresponds to a reactive extraction. The reactive extraction of an organic acid from the aqueous ammonium salt solution thereof can be improved significantly by the use of a stripping medium or entraining gas, for example nitrogen, air, steam or inert gases, for example argon. The ammonia released is removed from the aqueous solution by the continuous gas stream and can be fed back into a production process. The free acid can be obtained from the extractant by a process such as distillation, rectification, crystallization, re-extraction, chromatography, adsorption, or by a membrane process.
Synthesis of novel chiral Schiff bases and their application in asymmetric transfer hydrogenation of prochiral ketones
Zhou, Zhongqiang,Bian, Yongjun
scheme or table, p. 682 - 687 (2010/11/04)
Novel chiral Schiff bases were synthesized from (+)-camphor, and their application to asymmetric transfer hydrogenation of prochiral ketones is described. The asymmetric transfer hydrogenation reaction could afford excellent conversion rates (up to 97.3%) and up to 27.3% enantiomeric excess.
Polymorphic clopidogrel hydrogenesulphate form
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, (2008/06/13)
Novel orthorombic polymorph of clopidogrel hydrogen sulfate or hydrogen sulfate of methyl (+)-(S)-α-(2-chlorophenyl)-4,5,6,7-tetrahydrothieno[3,2-c]pyridine-5-acetate and a process for its preparation.
Dibenzonaphthyrones
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, (2008/06/13)
Dibenzonaphthyrone of formula (I) wherein A1and A2independently of each other are unsubstituted or mono- to tetra-substituted o-C6-C18arylene, with the proviso that formula (I) does not represent a dibenzonaphthyrone of the formula The invention further relates to processes for the preparation thereof, to the use thereof for colouring/pigmenting high-molecular-weight organic material and to substance compositions comprising dibenzonaphthyrones.
