2899-67-4Relevant academic research and scientific papers
Selective synthesis of α-organylthio esters and α-organylthio ketones from β-keto esters and sodium S-organyl sulfurothioates under basic conditions
Kazmierczak, Jean C.,Cargnelutti, Roberta,Barcellos, Thiago,Silveira, Claudio C.,Schumacher, Ricardo F.
supporting information, p. 234 - 244 (2021/02/27)
We described herein a selective method to prepare α-organylthio esters and α-organylthio ketones by the reaction of β-keto esters with sodium S-benzyl sulfurothioate or sodium S-alkyl sulfurothioate (Bunte salts) under basic conditions in toluene as the solvent at 100 °C. When 4 equivalents of a base were used, a series of differently substituted α-thio esters were obtained with up to 90% yield. On the other hand, employing 2 equivalents of a base, α-thio ketones were achieved after 18 h under air. Furthermore, after a shorter reaction time, the isolation of keto-enol tautomers was possible, revealing them as significant intermediates for the mechanism elucidation.
Air-stable binuclear Titanium(IV) salophen perfluorobutanesulfonate with zinc power catalytic system and its application to C–S and C–Se bond formation
Wang, Lingxiao,Qiao, Jie,Wei, Jiancong,Liang, Zhiwu,Xu, Xinhua,Li, Ningbo
, (2020/01/08)
An air-stable μ-oxo-bridged binuclear Lewis acid of titanium(IV) salophen perfluorobutanesulfonate [{Ti(salophen)H2O}2O][OSO2C4F9]2 (1) was successfully synthesized by the reaction of TiIV(salophen)Cl2 with AgOSO2C4F9 and characterized by techniques such as IR, NMR and HRMS. This complex was stable open to air over a year, and exhibited good thermal stability and high solubility in polar organic solvents. The complex also had relatively strong acidity with a strength of 0.8 Ho ≤ 3.3, and showed high catalytic efficiency towards various C–S and C–Se bond formations in the presence of zinc power. This catalytic system affords a mild and efficient approach to synthesis of thio- and selenoesters, α-arylthio- and seleno-carbonyl compounds, and thio- and selenoethers.
Scope and Mechanism of Iridium Porphyrin-Catalyzed S-H Insertion Reactions between Thiols and Diazo Esters
Dairo, Taiwo O.,Woo, L. Keith
, p. 927 - 934 (2017/04/21)
The insertion of carbenes derived from ethyl diazoacetate (EDA), methyl diazoacetate (MDA), methyl phenyldiazoacetate (MPDA), and methyl (p-tolyl)diazoacetate (MTDA) into the S-H bonds of aromatic and aliphatic thiols was catalyzed by (5,10,15,20-tetratolylporphyrinato)methyliridium(III), Ir(TTP)CH3, at ambient temperatures. Yields of the resulting thioether products were as high as 97% for aromatic thiols, with catalyst loadings as low as 0.07 mol %. Thiol binding to Ir(TTP)CH3 was measured at 23 °C by titration studies, providing equilibrium constants, Kb, ranging from 4.25 × 102 to 1.69 × 103 and increasing in the order p-nitrobenzenethiol a mechanism that involves a rate-limiting nucleophilic attack of thiols on an iridium-carbene species, where the major species present in the reaction solution is an inactive, hexacoordinate Ir-thiol complex.
MYOGLOBIN-BASED CATALYSTS FOR CARBENE TRANSFER REACTIONS
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Paragraph 00308; 00312; 00321, (2016/06/14)
Methods are provided for carrying out carbene transfer transformations such as olefin cyclopropanation reactions, carbene heteroatom-H insertion reactions (heteroatom = N, S, Si), sigmatropic rearrangement reactions, and aldehyde olefination reactions with high efficiency and selectivity by using a novel class of myoglobin-based biocatalysts. These methods are useful for the synthesis of a variety of organic compounds which contain one or more new carbon-carbon or carbon-heteroatom (N, S, or Si) bond. The methods can be applied for conducting these transformations in vitro (i.e., using the biocatalyst in isolated form) and in vivo (i.e., using the biocatalyst in a whole cell system).
Intermolecular carbene S-H insertion catalysed by engineered myoglobin-based catalysts
Tyagi, Vikas,Bonn, Rachel B.,Fasan, Rudi
, p. 2488 - 2494 (2015/03/30)
The first example of a biocatalytic strategy for the synthesis of thioethers via an intermolecular carbene S-H insertion reaction is reported. Engineered variants of sperm whale myoglobin were found to efficiently catalyze this C-S bond forming transformation across a diverse set of aryl and alkyl mercaptan substrates and α-diazoester carbene donors, providing high conversions (60-99%) and high numbers of catalytic turnovers (1100-5400). Furthermore, the enantioselectivity of these biocatalysts could be tuned through mutation of amino acid residues within the distal pocket of the hemoprotein, leading to myoglobin variants capable of supporting asymmetric S-H insertions with up to 49% ee. Rearrangement experiments support a mechanism involving the formation of a sulfonium ylide generated upon attack of the thiol substrate to a heme-bound carbene intermediate. This journal is
Fe-Mediated S-S Bond Cleavage and Its Application in the Synthesis of α-Arylthio Carbonyl Compounds
He, Yun-Hua,Li, Ning-Bo,Chen, Jin-Yang,Qiu, Ren-Hua,Wang, Xie,Xu, Xin-Hua
, p. 1817 - 1822 (2015/08/06)
In the presence of iron dust, diaryl disulfides react with α-bromo carbonyl compounds to obtain α-arylthio carbonyl compounds in good yield at 90 °C under an N2 atmosphere, using commercial dimethylformamide (DMF) as solvent. The possible reaction mechanism is that the disulfide is reduced by iron dust to give ArSFeSAr and then reacted with α-bromo carbonyl compounds to give product α-arylthio carbonyl compounds and FeBr2.
Facile synthesis of 3-benzylsulfinyl- and 3-benzylsulfonyl-7- diethylaminocoumarins
Wang, Xiaolong,Xue, Ziyan,Ma, Yanying,Yang, Fang
, p. 493 - 495 (2014/11/08)
The efficient synthesis of a 3-benzylsulfinylcoumarin and a 3-benzylsulfonylcoumarin starting from thiobenzyl alcohol using solvent-free Knoevenagel reaction as the key step is reported. Moreover, the molecular structure of 3-benzylsulfonyl-7-diethylamino
Crystal Structure of 3-(4-Methoxy-benzylidene)-isothiochroman-4-one
Akkurt,YIldIrIm,Kerbal,Bennani,Hadda, T. Ben,Chohan,McKee, Vickie
experimental part, p. 165 - 168 (2011/07/30)
The title compound, 3-(4-methoxy-benzylidene)-isothiochroman-4-one (C 17H14O2S) was prepared from the reaction of isothiochroman-4-one with benzaldehyde in the presence of small amount of HCl. The structure of the synthesised compound was determined by IR, 1H NMR and X-ray crystallography. The structure was solved in monoclinic, space group P21/n with a = 3.9773 (7) A, b = 10.918 (2) A, c = 30.609 (6) A, β = 90.615 (3)°, V = 1329.1 (4) A3, Z = 4 and with R int = 0.047. The bicyclic ring of isothiochroman-4-one moiety does not adopt a planar geometry. The molecular conformation is stable via C10-H???O1 and C16- H???S1 intramolecular hydrogen-bonding interactions. These contacts involve molecules in an extended two-dimensional sheet to the bc plane.
Synthesis of some novel bioactive 4-oxy/thio substituted-1H-pyrazol-5(4H)-ones via efficient cross-Claisen condensation
Venkat Ragavan,Vijayakumar,Suchetha Kumari
experimental part, p. 3852 - 3857 (2009/12/04)
α-Oxy/thio substituted-β-keto esters were synthesized through an efficient cross-Claisen condensation of aryl oxy/thio acetic acid ethyl esters with acid chlorides, then it is converted in situ into 4-oxy/thio substituted-1H-pyrazol-5(4H)-ones by the addition of hydrazine or hydrazine derivatives and screened for their antibacterial, antifungal activities.
Heterocyclic compounds as P2X7 ion channel blockers
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Page/Page column 77, (2010/02/10)
The present invention relates to a novel series of 4,5-diphenyl-2-amino-4,5-dihydro-imidazole derivatives of the formula II: 1 wherein R, R1, R2, R3, R4, R5, X and Y are as defined herein. This invention also relates to methods of making these compounds. The compounds of this invention are P2X7 ion channel blockers and are therefore useful as pharmaceutical agents, especially in the treatment and/or prevention of a variety of diseases having an inflammatory component, including inflammatory bowel disease, rheumatoid arthritis and disease conditions associated with the central nervous system, such as stroke, Alzheimer''s disease, etc.
