657-46-5Relevant academic research and scientific papers
Switchable Synthesis of Aryl Sulfones and Sulfoxides through Solvent-Promoted Oxidation of Sulfides with O2/Air
Cheng, Zhen,Sun, Pengchao,Tang, Ailing,Jin, Weiwei,Liu, Chenjiang
supporting information, p. 8925 - 8929 (2019/11/14)
A practical and switchable method for the synthesis of aryl sulfones and sulfoxides via sulfide oxidation was developed. The chemoselectivities of products were simply controlled by reaction temperature using O2/air as the terminal oxidant and oxygen source. The broad substrate scope, easy realization of gram-scale production, and the simplification of a sulfide oxidation system render the strategy attractive and valuable.
Electrophilic and nucleophilic pathways in ligand oxide mediated reactions of phenylsulfinylacetic acids with oxo(salen)chromium(V) complexes
Subramaniam,Sugirtha Devi,Anbarasan
, p. 164 - 173 (2016/06/06)
The mechanism of oxidative decarboxylation of phenylsulfinylacetic acids (PSAA) by oxo(salen)Cr(V)+ ion in the presence of ligand oxides has been studied spectrophotometrically in acetonitrile medium. Addition of ligand oxides (LO) causes a red shift in the λmax values of oxo(salen) complexes and an increase in absorbance with the concentration of LO along with a clear isobestic point. The reaction shows first-order dependence on oxo(salen)-chromium(V)+ ion and fractional-order dependence on PSAA and ligand oxide. Michaelis-Menten kinetics without kinetic saturation was observed for the reaction. The order of reactivity among the ligand oxides is picoline N-oxide > pyridine N-oxide > triphenylphosphine oxide. The low catalytic activity of TPPO was rationalized. Both electron-withdrawing and electron-donating substituents in the phenyl ring of PSAA facilitate the reaction rate. The Hammett plots are non-linear upward type with negative ρ value for electron-donating substituents, (ρ- = -0.740 to -4.10) and positive ρ value for electron-withdrawing substituents (ρ+ = +0.057 to +0.886). Non-linear Hammett plot is explained by two possible mechanistic scenarios, electrophilic and nucleophilic attack of oxo(salen)chromium(V)+-LO adduct on PSAA as the substituent in PSAA is changed from electron-donating to electron-withdrawing. The linearity in the log k vs. Eox plot confirms single-electron transfer (SET) mechanism for PSAAs with electron-donating substituents.
Dynamics of cetyltrimethylammonium bromide-mediated reaction of phenylsulfinylacetic acid with Cr(VI): Treatment of pseudo-phase models
Subramaniam, Perumal,Selvi, Natesan Thamil
, p. 1019 - 1034 (2015/11/27)
The influence of cetyltrimethylammonium bromide, CTAB, on the oxidative decarboxylation of phenylsulfinylacetic acid, PSAA, and several meta- and para-substituted PSAAs by Cr(VI) was investigated in 95 % H2O-5 % CH3CN medium. The rate profile displayed a peculiar trend with an initial rate increase at low CTAB followed by sharp rate inhibition at higher CTAB concentrations. The initial rate acceleration could be explained by strong binding of SO42- on the positively charged micellar surface. The specific partitioning of PSAA in the micellar phase by hydrophobic interaction and the oxidizing species HCrO3+ in aqueous phase by electrostatic repulsion accounted for the rate retardation at higher CTAB concentrations. The Hammett plot with different substituted PSAAs showed excellent correlation affording negative ? value, which supports the proposed mechanism involving the intermediate formation of sulfonium cation. The obtained ? value in CTAB medium was found to be slightly lower than that in aqueous medium. Quantitative analysis of the rate data for the inhibition shown by CTAB was performed using the Menger-Portnoy and the Piszkiewicz pseudo-phase models. The binding constant for PSAA with micelles was evaluated from the Piszkiewicz cooperative model.
Spectral and mechanistic investigation of Oxidative Decarboxylation of Phenylsulfinylacetic Acid by Cr(VI)
Subramaniam, Perumal,Selvi, Natesan Thamil,Devi, Soundarapandian Sugirtha
, p. 17 - 24 (2014/03/21)
The oxidative decarboxylation of phenylsulfinylacetic acid (PSAA) by Cr(VI) in 20% acetonitrile - 80% water (v/v) medium follows overall second order kinetics, first order each with respect to [PSAA] and [Cr(VI)] at constant [H+] and ionic strength. The reaction is acid catalysed, the order with respect to [H+] is unity and the active oxidizing species is found to be HCrO3+. The reaction mechanism involves the rate determining nucleophilic attack of sulfur atom of PSAA on chromium of HCrO3+ forming a sulfonium ion intermediate. The intermediate then undergoes a,β-cleavage leading to the liberation of CO2. The product of the reaction is found to be methyl phenyl sulfone. The operation of substituent effect shows that PSAA containing electron-releasing groups in the meta- and para-positions accelerate the reaction rate while electron withdrawing groups retard the rate. An excellent correlation is found to exist between log k2 and Hammett s constants with a negative value of reaction constant. The p value decreases with increase in temperature evidencing the high reactivity and low selectivity in the case of substituted PSAAs.
Copper-catalyzed aerobic oxidation and cleavage/formation of C-S bond: A novel synthesis of aryl methyl sulfones from aryl halides and DMSO
Yuan, Gaoqing,Zheng, Junhua,Gao, Xiaofang,Li, Xianwei,Huang, Liangbin,Chen, Huoji,Jiang, Huanfeng
supporting information; experimental part, p. 7513 - 7515 (2012/10/07)
With atmospheric oxygen as the oxidant, a novel copper(i)-catalyzed synthesis of aryl methyl sulfones from aryl halides and widely available DMSO is described. The procedure tolerates aryl halides with various functional groups (such as methoxy, acetyl, chloro, fluoro and nitro groups), which could afford aryl methyl sulfones in moderate to high yields. The copper-catalyzed aerobic oxidation and the cleavage/formation of C-S bond are the key steps for this transformation.
Quinazoline Compounds
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Page/Page column 41, (2010/12/26)
Disclosed are quinazoline-based modulators of Liver X receptors (LXRs) and related methods. The modulators include compounds of formula (I): in which R1, R2, R3, R4, R5, R6, R7,
Study of regioselective methanesulfonylation of simple aromatics with methanesulfonic anhydride in the presence of zeolite catalysts
Smith, Keith,Ewart, Gordon M.,El-Hiti, Gamal A.,Randles, Kenneth R.
, p. 3150 - 3154 (2007/10/03)
Regioselective methanesulfonylation of simple aromatics using methanesulfonic anhydride can be achieved over zeolite catalysts. For example, methanesulfonylation of toluene over various cation-exchanged zeolite β catalysts affords higher para-selectivity in the synthesis of methyl tolyl sulfone than standard Friedel Crafts methanesulfonylation utilising aluminium chloride.
Selective aromatic electrochemical fluorination of methyl phenyl sulfone
Shainyan,Danilevich,Bel'skii,Stash,Grigor'eva,Chuvashev
, p. 1462 - 1464 (2007/10/03)
Electrochemical fluorination of methyl phenyl sulfone occurs exclusively at the aromatic ring to give isomeric methyl mono- and difluorophenyl sulfones and methyl 3,3,6,6-tetrafluoro-1,4-cyclohexadienyl sulfone.
