85589-35-1Relevant academic research and scientific papers
Silica sulfuric acid as a highly efficient catalyst for the synthesis of diarylacetic acids
Moore, Desiree L.,Denton, Allison E.,Kohinke, Rose M.,Craig, Brandon R.,Brenzovich, William E.
supporting information, p. 604 - 612 (2016/07/06)
ABSTRACT: An efficient heterogeneous method for the synthesis of diarylacetic acids was developed utilizing silica sulfuric acid as a catalyst. The reaction is highly efficient with a small amount of catalyst for the combination of a variety of electron-n
Solid phase behavior in the chiral systems of various 2-hydroxy-2-phenylacetic acid (mandelic acid) derivatives
Von Langermann, Jan,Temmel, Erik,Seidel-Morgenstern, Andreas,Lorenz, Heike
, p. 721 - 728 (2015/03/30)
The solid phase behavior of a series of monosubstituted F-, Cl-, Br-, I-, and CH3- and two 2,4-halogen-disubstituted 2-hydroxy-2-phenylacetic acid (mandelic acid) derivatives was investigated. The study includes detailed information about melting temperature, melting enthalpy, X-ray diffraction data, as well as selected binary phase diagrams of the respective chiral systems. Aside from the known metastable conglomerate 2-chloromandelic acid, evidence for two more metastable conglomerates was found.
Kinetic resolution of mandelate esters via stereoselective acylation catalyzed by lipase PS-30
Chen, Peiran,Yang, Wenhong
supporting information, p. 2290 - 2294 (2014/04/17)
By using lipase PS-30 as catalyst, the kinetic resolution of a series of racemic mandelate esters has been achieved via stereoselective acylation. The value of kinetic enantiomeric ratio (E) reached up to 197.5. Substituent effect is briefly discussed.
Relationships between the racemic structures of substituted mandelic acids containing 8- and 10-membered hydrogen bonded dimer rings
Coles,Ellis,Leung,Sarson,Threlfall,Tizzard
, p. 10816 - 10823 (2015/02/19)
The structures of 27 monosubstituted mandelic acids, including several of their polymorphs, plus unsubstituted mandelic acid itself (two polymorphs) are investigated for structural similarity. The results, presented pictorially as a structural relationship plot, show that rather more structures are built up from the carboxyl-chain hydroxyl hydrogen bonded dimer than from the conventional carboxylic acid dimer. The results show how all the structures are related and, based on the two types of dimer, the degree of similarity that they possess. Some structures with Z′ > 1 contain both sorts of dimers and there are many examples of isostructural sets within the structures so far determined. We also present an example where analysing similarity in related families of structures highlights a structure that should be present and which has indeed then proceeded to be synthesised and determined.
Organocatalytic asymmetric synthesis of functionalized 1,3,5- triarylpyrrolidin-2-ones via an aza-Michael/aldol domino reaction
Joie, Celine,Deckers, Kristina,Enders, Dieter
, p. 799 - 808 (2014/04/03)
The organocatalytic asymmetric synthesis of functionalized 1,3,5-triarylpyrrolidin-2-ones bearing three contiguous stereocenters through an aza-Michael/aldol domino reaction of α-ketoamides with α,β-unsaturated aldehydes is described. The domino products
CeCl3·7H2O: An effective additive in ru-catalyzed enantioselective hydrogenation of aromatic α-ketoesters
Meng, Qinghua,Sun, Yanhui,Ratovelomanana-Vidal, Virginie,Genet, Jean Pierre,Zhang, Zhaoguo
, p. 3842 - 3847 (2008/09/21)
(Chemical Equation Presented) In the presence of catalytic amounts of CeCl3·7H2O, [RuCl(benzene)(S)-SunPhos]Cl is a highly effective catalyst for the asymmetric hydrogenation of aromatic α-ketoesters. A variety of ethyl α-hydroxy-α-arylacetates have been prepared in up to 98.3% ee with a TON up to 10 000. Challenging aromatic α-ketoesters with ortho substituents are also hydrogenated with high enantioselectivities. The addition of CeCl3·7H2O not only improves the enantioselectivity but also enhances the stability of the catalyst. The ratio of CeCl3·7H2O to [RuCl(benzene)(S)-SunPhos]Cl plays an important role in the hydrogenation reaction with a large substrate/catalyst ratio.
Lipase-catalyzed enantioselective transesterification toward esters of 2-bromo-tolylacetic acids
Guieysse, David,Salagnad, Christophe,Monsan, Pierre,Remaud-Simeon, Magali
, p. 317 - 323 (2007/10/03)
Lipases from Candida antarctica, Pseudomonas cepacia and Rhizomucor miehei were tested in the resolution of seven racemic substrates belonging to the (RS)-2-bromo tolyl acetate ester category, but differing either in the position of the methyl substituent on the acyl part of the aromatic ring, or in the structure of the alkyl group. Lipase-catalyzed kinetic resolution via transesterification reaction between the ester and octanol in octane revealed that, of the three enzymes tested, P. cepacia lipase is the most efficient for resolution of the various racemates, with R-enantiopreference. In addition, the position of the methyl substituent was found to play a key role in governing the enantioselectivity of the reaction. Using P. cepacia lipase and 2-bromo-m/p-tolyl- or 2-bromophenylacetic acid esters E-values of 6.
Selective ET(A) antagonists. 5. Discovery and structure-activity relationships of phenoxyphenylacetic acid derivatives
Astles, Peter C.,Brown, Thomas J.,Halley, Frank,Handscombe, Caroline M.,Harris, Neil V.,Majid, Tahir N.,McCarthy, Clive,McLay, Lain M.,Morley, Andrew,Porter, Barry,Roach, Alan G.,Sargent, Carol,Smith, Christopher,Walsh, Roger J. A.
, p. 900 - 910 (2007/10/03)
The fifth paper in this series describes the culmination of our investigations into the development of a potent and selective ETA receptor antagonist for the treatment of diseases mediated by ET-1. Receptor site mapping of several ETA antagonists prepared previously identified a common cationic binding site which prompted synthesis of phenoxyphenylacetic acid derivative 13a, which showed good in vitro activity (IC50 59 nM, rat aortic ET(A)). Optimization of 13a led to the identification of 27b, which exhibited an IC50 of 4 nM. Although this did not translate into the expected in vivo potency, a compound of comparable in vitro activity, 27a (RPR118031A), showed a far better pharmacokinetic profile and in vivo potency (75 μmol/kg) and was duly proposed and accepted as a development candidate.
Reaction of carboxylic acids with diethyl phosphorocyanidate; a novel synthesis of homologated α-hydroxycarboxylic acids from carboxylic acids
Mizuno, Masanori,Shioiri, Takayuki
, p. 9209 - 9210 (2007/10/03)
Carboxylic acids react with 2 equivalents of diethyl phosphorocyanidate in the presence of triethylamine to give dicyanophosphates in good yields; these dicyanophosphates can be hydrolyzed easily to give homologated α- hydroxycarboxylic acids.
Rearrangement of 2-(Arylmethoxy)methyl-2-oxazolines via Lithium Azaenolates: a Facile Synthetic Route to ortho-Methylmandelic Acid Derivatives
Kamata, Kazuyuki,Terashima, Masanao
, p. 2771 - 2772 (2007/10/02)
2-(Arylmethoxy)methyl-2-oxazolines, on treatment with LDA in THF at low temperature, rearrange to afford products which are hydrolysed to ortho-methylmandelic acids or α-(1-methyl-2-naphthyl)glycolic acid.
