115794-66-6Relevant articles and documents
A new chiral diiron catalyst for enantioselective epoxidation
Marchi-Delapierre, Caroline,Jorge-Robin, Adeline,Thibon, Aurore,Menage, Stephane
, p. 1166 - 1168 (2007)
The dinuclear chiral complex Fe2O(bisPB)4(X) 2(ClO4)4 (X = H2O or CH 3CN) catalyzes with high efficiency (up to 850 TON) and moderate enantioselectivity (63%) the epoxidation of
Efficient magnetic and recyclable SBILC (supported basic ionic liquid catalyst)-based heterogeneous organocatalysts for the asymmetric epoxidation of trans-methylcinnamate
Candu,Rizescu,Podolean,Tudorache,Parvulescu,Coman
, p. 729 - 737 (2015)
A green alternative, based on the use of an efficient and recyclable chiral ketone@SBILC@MWCNT@Fe3O4 catalytic system (Y = 35%, S = 100% and ee = 100%), was developed for the asymmetric epoxidation of trans-methylcinnamate to (2R,3S)
Postsynthetic modification of a metal-organic framework (MOF) structure for enantioselective catalytic epoxidation
Candu, Natalia,Tudorache, Madalina,Florea, Mihaela,Ilyes, Elena,Vasiliu, Florin,Mercioniu, Ionel,Coman, Simona M.,Haiduc, Ionel,Andruh, Marius,Parvulescu, Vasile I.
, p. 443 - 450 (2013)
Postsynthetic modification of [Cu2(mand)2(hmt)] (mand=mandelic acid, hmt=hexamethylenetetramine) with a chiral, dimeric chromium(III)-salen complex led to a robust structure. Characterization of this new material showed that it perfectly preserved the textural and structural properties of the parent metal-organic framework (MOF). Although epoxidation of trans-methyl cinnamate with hydrogen peroxide led to copper leaching of 2-3 %, experiments performed with N-methylmorpholine-N-oxide indicated no leaching, even after 72 h of exposure. The obtained chiral MOF is an effective catalyst for the enantioselective epoxidation of trans-methyl cinnamate and leads to (2R,3S)-phenylglycidate with a high enantiomeric excess at room temperature. Transformed and ready for action! Postsynthetic modification of [Cu 2(mand)2(hmt)] (mand=mandelic acid, hmt= hexamethylenetetramine) results in an effective catalyst (see picture) for the enantioselective epoxidation of trans-methyl cinnamate to provide methyl (2R,3S)-phenylglycidate with a high ee value at room temperature. Copyright
Synthesis of enantiomerically pure forms of trans-3-phenylglycidic acid.
Plucinska, Krystyna,Kasprzykowski, Franciszek,Kozian, Elzbieta
, p. 861 - 864 (1997)
Trans-(2R,3S)- and (2S,3R)-3-phenylglycidic acids were obtained as pure crystals. The optical properties and chemical stability were characterized. The absolute configuration of the trans(+)- and trans-(-) isomers was established by means of chemical correlation.
Dioxirane-mediated heterogeneous epoxidations with potassium caroate: A solid catalyst bearing anchored ketone moieties
D'Accolti, Lucia,Annese, Cosimo,De Riccardis, Alberto,De Giglio, Elvira,Cafagna, Damiana,Fanelli, Fiorenza,Fusco, Caterina
, p. 4616 - 4621,6 (2012)
A new hybrid material (3) consisting of trifluoromethyl ketone (TFMK) moieties, immobilized on silica through an appropriate spacer, was synthesized and characterized. Lacking easily oxidizable functionalities in the spacer chain, this material proved to be an excellent catalyst in heterogeneous epoxidations with potassium caroate (KHSO5), surpassing other reported catalysts in performance and stability. The efficiency of silica-supported catalyst 3 could be assessed upon carrying out the selective dioxirane-mediated epoxidation of representative alkenes in high yields. The solid catalyst could then be recovered and reused in a number of consecutive oxidation cycles. The synthesis of a new hybrid, which presents trifluoromethyl ketone moieties anchored on silica gel through a short spacer, is reported. Lacking easily oxidizable functionalities in the linker chain, this solid material is an efficient catalyst in dioxirane-mediated heterogeneous epoxidations using potassium caroate. Copyright
Regioselective syntheses of 3-hydroxy-4-aryl-3,4,5-trihydro-2H-benzo[b][1,4]diazepin-2(1H)-ones and 3-benzylquinoxalin-2(1H)-ones from arylglycidates when exposed to 1,2-diaminobenzenes
Mamedov, Vakhid A.,Mamedova, Vera L.,Syakaev, Victor V.,Voronina, Julia K.,Mahrous, Essam M.,Korshin, Dmitry E.,Latypov, Shamil K.,Sinyashin, Oleg G.
, (2020/09/10)
Representatives of two pharmacologically significant classes of compounds – 3-hydroxy-4-aryl-3,4,5-trihydro-2H-benzo[b][1,4]diazepin-2(1H)-ones and 3-benzylquinoxalin-2(1H)-ones – obtained in reactions of 1,2-diaminobenzenes with methyl 3-arylglycidates in boiling acetic acid. Substituents in arylglycidates determine the direction of processes. Electron withdrawing substituents (NO2), halogen atoms (Cl, Br, F), as well as the absence of substituents, provide the formation of benzo[b][1,4]diazepin-2(1H)-one derivatives, and electron donating groups (OMe, Me) contribute to the formation of 3-benzylquinoxalin-2(1H)-ones. As a result, a new rare representatives of 3-hydroxy-4-aryl-3,4,5-trihydro-2H-benzo[b][1,4]diazepin-2(1H)-ones were obtained and a new method for producing 3-benzylquinoxalin-2(1H)-ones has been proposed.
Intermolecular Amine Transfer to Enantioenriched trans-3Phenylglycidates by an α/β-Aminomutase to Access Both anti-Phenylserine Isomers
Shee, Prakash K.,Yan, Honggao,Walker, Kevin D.
, p. 15071 - 15082 (2020/12/21)
β-Hydroxy-α-amino acids are noncanonical amino acids with two stereocenters and with useful applications in the pharmaceutical and agrochemical sectors. Here, a 5-methylidene-3,5-dihydro-4H-imidazol-4-one-dependent aminomutase from Taxus canadensis (TcPAM) was repurposed to transfer the amino group irreversibly from (2S)-styryl-α-alanine to exogenously supplied trans-3-phenylglycidate enantiomers, producing anti-phenylserines stereoselectively. TcPAM catalysis inverted the intrinsic regioselective chemistry from amination at Cβ to Cα of enantioenriched trans-3-phenylglycidates to make phenylserine predominantly (97%)phenylisoserine (～3% relative abundance). Gas chromatography?mass spectrometry analysis of the chiral auxiliary derivatives of the biocatalyzed products confirmed that the amine transfer was stereoselective for each glycidate enantiomer. TcPAM converted (2S,3R)-3-phenylglycidate to (2S)-anti-phenylserine predominantly (89%) and (2R,3S)-3-phenylglycidate to (2R)-anti-phenylserine (88%)their antipodes, with inversion of the configuration at Cα in each case. Both glycidate enantiomers formed a small amount (～10%) of syn-phenylserine by retaining the configuration at Cα. The minor syn-isomer likely came from a β-hydroxy oxiranone intermediate formed by intramolecular ring opening of the oxirane ring by the carboxylate before amine transfer. TcPAM had a slight preference toward (2S,3R)-3-phenylglycidate, which was turned(kcat = 0.3 min?1) 1.5 times faster than the (2R,3S)-glycidate (kcat = 0.2 min?1). The catalytic efficiencies (kcatapp/KMapp ≈ 20 M?1s?1) of TcPAM for the antipodes were similar. The kinetic data supported a two-substrate ping-pong mechanism for the amination of the phenylglycidates, with competitive inhibition at higher glycidate substrate concentrations.
Enantiomeric resolution, thermodynamic parameters, and modeling of clausenamidone and neoclausenamidone on polysaccharide-based chiral stationary phases
Luo, Xuna,Fang, Chengqiao,Mi, Junru,Xu, Jingzi,Lin, Hansen
, p. 423 - 433 (2019/05/07)
The aim of the paper is to describe a new synthesis route to obtain synthetic optically active clausenamidone and neoclausenamidone and then use high-performance liquid chromatography (HPLC) to determine the optical purities of these isomers. In the process, we investigated the different chromatographic conditions so as to provide the best separation method. At the same time, a thermodynamic study and molecular simulations were also carried out to validate the experimental results; a brief probe into the separation mechanism was also performed. Two chiral stationary phases (CSPs) were compared with separate the enantiomers. Elution was conducted in the organic mode with n-hexane and iso-propanol (IPA) (80/20?v/v) as the mobile phases; the enantiomeric excess (ee) values of the synthetic R-clausenamidone and S-clausenamidone and R-neoclausenamidone and S- neoclausenamidone were higher than 99.9%, and the enantiomeric ratio (er) values of these isomers were 100:0. Enantioselectivity and resolution (α and Rs, respectively) levels with values ranging from 1.03 to 1.99 and from 1.54 to 17.51, respectively, were achieved. The limits of detection and quantitation were 3.6 to 12.0 and 12.0 to 40.0 ug/mL, respectively. In addition, the thermodynamics study showed that the result of the mechanism of chiral separation was enthalpically controlled at a temperature ranging from 288.15 to 308.15?K. Furthermore, docking modeling showed that the hydrogen bonds and π-π interactions were the major forces for chiral separation. The present chiral HPLC method will be used for the enantiomeric resolution of the clausenamidone derivatives.
