13991-52-1Relevant articles and documents
A phosphonium ylide as a visible light organophotoredox catalyst
Toda, Yasunori,Tanaka, Katsumi,Matsuda, Riki,Sakamoto, Tomoyuki,Katsumi, Shiho,Shimizu, Masahiro,Ito, Fuyuki,Suga, Hiroyuki
supporting information, p. 3591 - 3594 (2021/04/14)
A phosphonium ylide-based visible light organophotoredox catalyst has been designed and successfully applied to halohydrin synthesis using trichloroacetonitrile and epoxides. An oxidative quenching cycle by the ylide catalyst was established, which was confirmed by experimental mechanistic studies.
MBA-cross-linked poly(N-vinyl-2-pyrrolidone)/ferric chloride macromolecular coordination complex as a novel and recyclable Lewis acid catalyst: Synthesis, characterization, and performance toward for regioselective ring-opening alcoholysis of epoxides
Rahmatpour, Ali,Zamani, Maryam
, (2021/09/30)
A novel macromolecular-metal coordination complex, MBA-cross-linked PNVP/FeCl3 material was fabricated by immobilization of water intolerant ferric chloride onto the porous cross-linked poly(N-vinyl-2-pyrrolidone) carrier beads as a macromolecular ligand or carrier which was prepared by suspension free-radical copolymerization of N-vinyl-2-pyrrolidone (NVP) and N,N′-methylene bis-acrylamide (MBA) as a crosslinking agent in water. The obtained PNVP/FeCl3 was characterized by UV/vis and FT-IR spectroscopies, TGA, FE-SEM, EDX, and ICP techniques. This heterogenized version of ferric chloride is a convenient and safe alternative to highly water intolerant ferric chloride. The catalytic performance of (PNVP/FeCl3) as an efficient and recyclable polymeric Lewis acid catalyst was appropriately probed in the regio-and stereoselective nucleophilic ring opening of various epoxides with various alcohols in excellent yields with TOF up to 182.48 h?1 without generating any waste. The activity data indicate that this heterogeneous catalyst is very active and could be easily recovered, and reused at least six times without appreciable loss of activity indicating its stability under experimental conditions.
SULFONIMIDAMIDE COMPOUNDS AS NLRP3 MODULATORS
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Paragraph 0784, (2021/07/31)
Described herein are compounds of Formula (I), Formula (I-A), and Formula (I-B), solvates thereof, tautomers thereof, and pharmaceutically acceptable salts of the foregoing, Further described herein are methods of inhibiting NLRP3 using said compounds, and methods of and compositions useful in treating NLRP3-dependent disorders.
Selective monochlorination of unsymmetrical vicinal diols with chlorinated iminium chlorides
Li, Chengyang,Li, Xiaotong,Wang, Yu,Wu, Xiaoyu,Xie, Xiaomin,Yang, Liqun,Zhang, Zhaoguo
, (2020/03/23)
Chlorinated iminium chlorides have been identified to promote the highly efficient and selective mono-chlorination of unsymmetrical vicinal diols. Vilsmeier reagent, namely, (chloromethylene)dimethyliminium chloride, enables highly reactive and regioselective chlorination of 1,2- and 1,3-diols featured one secondary benzylic hydroxy group and one primary aliphatic hydroxy group to give the corresponding 1,2- and 1,3-chlorohydrins. Viehe's salts (α,α-dichloro iminium salts) exhibit excellent reactivity and good selectivity for vicinal diols to give the corresponding chlorohydrin carbamates via a cyclic intermediate in situ. The chlorination protocols tolerate diverse functional groups, including halogens, naphthalene rings, nitro, and cyano. Moreover, the optical purity of chiral diols could be retained during this chlorination reaction.
Visible-light-triggered Catalytic Halohydrin Synthesis from Epoxides and Trichloroacetonitrile by Copper and Iron Salts
Toda, Yasunori,Tanaka, Katsumi,Matsuda, Riki,Suga, Hiroyuki
supporting information, p. 1469 - 1471 (2019/12/02)
Preparation of vicinal halohydrins, in which copper or iron chlorides catalyze the ring-opening reaction of epoxides with visible light effectively, is described. The use of trichloroacetonitrile as a halogen source enables catalytic HCl generation under the mild conditions. This method can also be applied to the aziridine ring-opening reaction.
An epoxide ring-opening reaction by using sol–gel-synthesized palladium supported on a strontium hydroxyl fluoride catalyst
Acham, Vaibhav R.,Dongare, Mohan K.,Kemnitz, Erhard,Umbarkar, Shubhangi B.
, p. 1237 - 1246 (2016/10/13)
Palladium supported on a strontium hydroxyl fluoride catalyst was synthesized by a one-pot fluorolytic sol–gel method. The prepared catalyst was characterized by various physicochemical techniques. The sol–gel method has led to the formation of a high surface area (57?m2g?1), mesoporous (pore diameter?=?13.0?nm) catalyst with uniform dispersion of Pd nanoparticles of size ～7?nm on the surface of strontium hydroxyl fluoride. The catalyst was used for epoxide alcoholysis, and 100% conversion was obtained with 96% selectivity for β-alkoxy alcohols under mild conditions. The catalyst could be recycled for up to three catalytic cycles without any appreciable decrease in conversion and selectivity, indicating the stability of the catalyst under the reaction conditions. Further, the mechanism of alcoholysis was proposed on the basis of the physicochemical characteristics of the catalyst and on the basis of the products formed during the catalytic reaction.
Efficient and regioselective ring-opening of epoxides with alcohols and sodium azide by using catalytic amounts of gacl3/polyvinylpyrrolidone
Pourali, Ali Reza,Ghayeni, Samaneh,Afghahi, Fatemeh
, p. 1741 - 1744 (2013/07/26)
A new polymeric catalyst was prepared by supporting GaCl3 on cross-linked polyvinylpyrrolidone (GaCl3/ PVP). This catalyst was employed for efficient and regioselective ring-opening reaction of epoxides by various alcohols under solvent-free conditions at room temperature. In our procedure, this heterogeneous catalyst was used at neutral and mild reaction conditions to afford high yields of β-alkoxy alcohols. Also, regioselective conversion of epoxides to β-azidohydrines was accomplished by sodium azide in MeOH in the presence of GaCl3/PVP at room temperature. GaCl3/PVP is a non-hygroscopic and recoverable catalyst and is easily separated from reaction mixture by a simple filtration and re-used repeatedly. Also, this catalyst has good handling and can be stored for long time without any reducing of its reactivity.
"Metal ion electrophilic catalysis" in ring-opening reactions of 1,2-epoxides by metal halides in ionic liquids
Betti, Cecilia,Landini, Dario,Maia, Angelamaria
, p. 1335 - 1338 (2007/10/03)
Metal ion electrophilic catalysis (Li+ > Na+ ? K+) has been found in ring-opening reactions of 1,2-epoxides 1-5 by metal halides MHa1 in ionic liquids. The results have been rationalized on the basis of a transition state where the cation M+ stabilizes the negative charge developing on the oxygen atom of the oxirane ring while favoring the nucleophilic attack at the adjacent carbon by the ion-paired anion Hal -. Georg Thieme Verlag Stuttgart.
Facile and regioselective conversion of epoxides into β-chlorohydrins using ZrCl4
Smitha,Reddy, Ch. Sanjeeva
, p. 300 - 301 (2007/10/03)
Epoxides were efficiently converted into the corresponding β-chlorohydrins in good yields by treatment with ZrCl4 in acetonitrile.
1,2-Ferrocenediylazaphosphinines 2: A new class of nucleophilic catalysts for ring-opening of epoxides
Paek, Seung Hwan,Shim, Sang Chul,Cho, Chan Sik,Kim, Tae-Jeong
, p. 849 - 851 (2007/10/03)
1,2-Ferrocenediylazaphosphinines (1a-c) have been successfully employed as a new class of nucleophilic catalysts for ring-opening of a range of epoxides, their catalytic efficiency in terms of regioselectivity as well as chemical yield comparing well with the existing catalysts in the literature. In contrast, low enantiomeric excesses have been obtained from the reactions of meso-epoxides catalyzed by (R)-1.
