515-30-0Relevant academic research and scientific papers
Electrochemical synthesis of α-hydroxycarboxylic acids from acetophenones
Khaja Lateef,Ramesh Raju,Krishna Mohan,Jayarama Reddy
, p. 31 - 36 (2006)
α-Hydroxy carboxylic acids are synthesized in 80-86% isolated yields by electrochemical carboxylation of methyl aryl ketones in the presence of carbon dioxide (1 atm.) using a platinum cathode and a sacrificial magnesium anode at a constant current density of 10 mA/cm2. Reversibility of the carbonyl group reduction and generation of anionic radical were shown by cyclic voltammetry. Copyright Taylor & Francis LLC.
Synthesis of α-hydroxycarboxylic acids from various aldehydes and ketones by direct electrocarboxylation: A facile, efficient and atom economy protocol
Singh, Kishanpal,Sohal, Harvinder Singh,Singh, Baljit
, p. 839 - 845 (2021/04/09)
In present work, the formation of α-hydroxycarboxylic acids have been described from various aromatic aldehydes and ketones via direct electrocarboxylation method with 80-92% of yield without any side product and can be purified by simple recrystallization using sacrificial Mg anode and Pt cathode in an undivided cell, CO2at (1 atm) was continuously bubbled in the cell throughout the reaction using tetrapropylammonium chloride as a supporting electrolyte in acetonitrile. The synthesized compounds obtained in fair to excellent yield with a high level of purity. The characterization of electrocarboxylated compounds was done with spectroscopic techniques like IR, NMR (1H & 13C), mass and elemental analysis.
Isothiourea-Catalyzed Acylative Kinetic Resolution of Tertiary α-Hydroxy Esters
Greenhalgh, Mark D.,Laina-Martín, Víctor,Neyyappadath, Rifahath M.,Qu, Shen,Smith, Andrew D.,Smith, Samuel M.
supporting information, p. 16572 - 16578 (2020/09/09)
A highly enantioselective isothiourea-catalyzed acylative kinetic resolution (KR) of acyclic tertiary alcohols has been developed. Selectivity factors of up to 200 were achieved for the KR of tertiary alcohols bearing an adjacent ester substituent, with both reaction conversion and enantioselectivity found to be sensitive to the steric and electronic environment at the stereogenic tertiary carbinol centre. For more sterically congested alcohols, the use of a recently-developed isoselenourea catalyst was optimal, with equivalent enantioselectivity but higher conversion achieved in comparison to the isothiourea HyperBTM. Diastereomeric acylation transition state models are proposed to rationalize the origins of enantiodiscrimination in this process. This KR procedure was also translated to a continuous-flow process using a polymer-supported variant of the catalyst.
A Bifunctional Iron Nanocomposite Catalyst for Efficient Oxidation of Alkenes to Ketones and 1,2-Diketones
Ma, Zhiming,Ren, Peng,Song, Tao,Xiao, Jianliang,Yang, Yong,Yuan, Youzhu
, p. 4617 - 4629 (2020/05/19)
We herein report the fabrication of a bifunctional iron nanocomposite catalyst, in which two catalytically active sites of Fe-Nx and Fe phosphate, as oxidation and Lewis acid sites, were simultaneously integrated into a hierarchical N,P-dual doped porous carbon. As a bifunctional catalyst, it exhibited high efficiency for direct oxidative cleavage of alkenes into ketones or their oxidation into 1,2-diketones with a broad substrate scope and high functional group tolerance using TBHP as the oxidant in water under mild reaction conditions. Furthermore, it could be easily recovered for successive recycling without appreciable loss of activity. Mechanistic studies disclose that the direct oxidation of alkenes proceeds via the formation of an epoxide as intermediate followed by either acid-catalyzed Meinwald rearrangement to give ketones with one carbon shorter or nucleophilic ring-opening to generate 1,2-diketones in a cascade manner. This study not only opens up a fancy pathway in the rational design of Fe-N-C catalysts but also offers a simple and efficient method for accessing industrially important ketones and 1,2-diketones from alkenes in a cost-effective and environmentally benign fashion.
An efficient synthetic approach towards fully functionalized tetronic acids: The use of 1,3-dioxolane-2,4-diones as novel protected-activated synthons of α-hydroxy acids
Prousis, Kyriakos C.,Markopoulos, John,Mckee, Vickie,Igglessi-Markopoulou, Olga
, p. 8637 - 8648 (2015/10/19)
A new strategy for the synthesis of tetronic acids with control over the regioselective introduction of substituents at the C-5 position has been developed. The construction of the densely functionalized quaternary carbon center within these molecules is of great importance. The key element for the proposed protocol was the utilization of O-carboxyanhydrides (OCA's) of optically active α-hydroxy acids, as promising bidentate protective/activating precursors. The structure of the new compounds was investigated by using NMR spectral data and X-ray structural analyses.
Evaluation of dalbavancin as chiral selector for HPLC and comparison with teicoplanin-based chiral stationary phases
Zhang, Xiaotong,Bao, Ye,Huang, Ke,Barnett-Rundlett, Kimber L.,Armstrong, Daniel W.
experimental part, p. 495 - 513 (2010/08/20)
Dalbavancin is a new compound of the macrocyclic glycopeptide family. It was covalently linked to 5 lm silica particles using two different binding chemistries. Approximately 250 racemates including (a) heterocyclic compounds, (b) chiral acids, (c) chiral amines, (d) chiral alcohols, (e) chiral sulfoxides and sulfilimines, (f) amino acids and amino acid derivatives, and (g) other chiral compounds were tested on the two new chiral stationary phases (CSPs) using three different mobile phases. As dalbavancin is structurally related to teicoplanin, the same set of chiral compounds was screened on two commercially available teicoplanin CSPs for comparison. The dalbavancin CSPs were able to separate some enantiomers that were not separated by the teicoplanin CSPs and also showed improved separations for many racemates. However, there were other compounds only separated or better separated on teicoplanin CSPs. Therefore, the dalbavancin CSPs are complementary to the teicoplanin CSPs.
HEPATITIS C VIRUS INHIBITORS
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Page/Page column 130, (2010/12/26)
The present disclosure relates to compounds, compositions and methods for the treatment of hepatitis C virus (HCV) infection. Also disclosed are pharmaceutical compositions containing such compounds and methods for using these compounds in the treatment of HCV infection.
Ag-TiO2/clay composite photocatalyst for the oxidation-cyclization of 1,2-diamine compounds with propylene glycol or alcohols
Selvam, Kaliyamoorthy,Annadhasan, Mari,Velmurugan, Rengasamy,Swaminathan, Meenakshisundaram
experimental part, p. 831 - 837 (2010/09/06)
Silver-loaded TiO2 (Ag-TiO2) and acidic clay (K10 montmorillonite) composite photocatalyst has been successfully applied for the light-induced conversion of o-phenylenediamine (OPD) and its derivatives to substituted benzimidazoles with various alcohols in acetonitrile using UV-A and solar light. The influence of the various photocatalysts, solvents, and substituents on the yield and selectivity of the products has been investigated. The mechanism of photocatalysis is proposed. Loading silver on TiO2 enhances product yield and selectivity both in UV and solar light. In the presence of primary alcohols, 2-aminothiophenol forms only disulfide and hence Ag-TiO2/ clay can be used as a green catalyst for the synthesis of disulfides.
Facile one-pot preparation of 2-arylpropionic and arylacetic acids from cyanohydrins by treatment with aqueous HI
Aramini, Andrea,Sablone, Manolo R.,Bianchini, Gianluca,Amore, Alessia,Fanì, Michela,Perrone, Plinio,Dolce, Alberto,Allegretti, Marcello
experimental part, p. 2015 - 2021 (2009/07/04)
A novel one-pot two-step procedure has been developed to synthesize highly substituted 2-arylpropionic and arylacetic acids, by treatment with aqueous HI, from cyanohydrins. The hydrogenolytic reduction of α-hydroxy-2-arylpropionic acids was the key step of the process and the optimization of the reaction conditions led to identify aqueous HI as an appropriate and selective reagent for the reductive deoxygenation of cyanohydrins. The synthetic route described a general and efficient strategy for the preparation of large libraries of phenylacetic and phenylpropionic acids derivatives.
A general synthesis of 2-alkoxy-2-phenylpropanoic acids
Monk, Keith A.,Duncan, Nathan C.,Bauch, Eric A.,Garner, Charles M.
, p. 8605 - 8609 (2008/12/21)
A preparation of a variety of 2-alkoxy-2-phenylpropanoic acids in two steps is described. Epoxidation of α-methylstyrene with mCPBA in methanol or primary alcohol solvents proceeded with an acid-catalyzed in situ ring opening reaction to give the corresponding 2-alkoxy-2-phenyl-1-propanols in 28-91% yield. Lower yields were realized with secondary (22-58%) and tertiary (14%) alcohols. These alcohols were cleanly oxidized to the corresponding carboxylic acids using a mild Heyns' oxidation (O2, Pt/C) in generally good to excellent yields (25-92%). The derived (S)-α-methylbenzylamide diastereomers are nearly all well separated by capillary GC, and the use of this method to determine the enantiomeric purity of brucine-resolved 2-methoxy-2-phenylpropanoic acid was demonstrated.
