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
Epoxidation of Alkenes with Molecular Oxygen as the Oxidant in the Presence of Nano-Al 2O 3
Zhou, Xuan,Wang, Qiong,Xiong, Wenfang,Wang, Lu,Ye, Rongkai,Xiang, Ge,Qi, Chaorong,Hu, Jianqiang
supporting information, p. 1789 - 1794 (2020/09/18)
The nano-Al 2O 3-promoted epoxidation of alkenes with molecular oxygen as the oxidant has been developed, providing an efficient route to a variety of epoxides in moderate to excellent yields. The environmentally friendly and efficient nano-Al 2O 3catalyst could be easily recovered and reused five times without significant loss of activity.
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.
Controlling Selectivity in Alkene Oxidation: Anion Driven Epoxidation or Dihydroxylation Catalysed by [Iron(III)(Pyridine-Containing Ligand)] Complexes
Tseberlidis, Giorgio,Demonti, Luca,Pirovano, Valentina,Scavini, Marco,Cappelli, Serena,Rizzato, Silvia,Vicente, Rubén,Caselli, Alessandro
, p. 4907 - 4915 (2019/08/30)
A highly reactive and selective catalytic system comprising Fe(III) and macrocyclic pyridine-containing ligands (Pc-L) for alkene oxidation by using hydrogen peroxide is reported herein. Four new stable iron(III) complexes have been isolated and characterized. Importantly, depending on the anion of the iron(III) metal complex employed as catalyst, a completely reversed selectivity was observed. When X=OTf, a selective dihydroxylation reaction took place. On the other hand, employing X=Cl resulted in the epoxide as the major product. The reaction proved to be quite general, tolerating aromatic and aliphatic alkenes as well as internal or terminal double bonds and both epoxides and diol products were obtained in good yields with good to excellent selectivities (up to 93 % isolated yield and d.r.=99 : 1). The catalytic system proved its robustness by performing several catalytic cycles, without observing catalyst deactivation. The use of acetone as a solvent and hydrogen peroxide as terminal oxidant renders this catalytic system appealing.
