14212-53-4Relevant articles and documents
Enantioselective oxidation of olefins catalyzed by a chiral bishydroxamic acid complex of molybdenum
Barlan, Allan U.,Basak, Arindrajit,Yamamoto, Hisashi
, p. 5849 - 5852 (2006)
(Chemical Equation Presented) Excellent yields and enantioselectivities can be achieved in the molybdenum-bishydroxamic acid catalyzed asymmetric oxidation of olefins in air at room temperature with an achiral oxidant (see scheme; acac = acetylacetonate).
Enantioselective epoxidation of conjugated Z-olefins with newly modified Mn(salen) complex
Egami, Hiromichi,Irie, Ryo,Sakai, Ken,Katsuki, Tsutomu
, p. 46 - 47 (2007)
Chiral Mn(salen) complex 3 bearing a 1-ethyl-1-methyl-propyl group at C3, C3′, C5, and C5′ was found to induce higher asymmetry in the epoxidation of conjugated Z-olefins, especially less nucleophilic ones, in the presence of 4-phenylpyridine N-oxide than
Natural Deep Eutectic Solvents as Performance Additives for Peroxygenase Catalysis
Ma, Yunjian,Li, Yongru,Ali, Shahid,Li, Peilin,Zhang, Wuyuan,Rauch, Marine C. R.,Willot, Sébastien J.-P.,Ribitsch, Doris,Choi, Young Hae,Alcalde, Miguel,Hollmann, Frank,Wang, Yonghua
, p. 989 - 994 (2020)
Natural deep eutectic solvents (NADES) are proposed as alternative solvents for peroxygenase-catalysed oxyfunctionalization reactions. Choline chloride-based NADES are of particular interest as they can serve as solvent, enzyme-stabiliser and sacrificial electron donor for the in situ H2O2 generation. This report provides the first proof-of-concept and basic characterisation of this new reaction system. Highly promising turnover numbers for the biocatalysts of up to 200,000 have been achieved.
Substrate enantioselectivity in the rabbit liver microsomal epoxide hydrolase catalyzed hydrolysis of trans and cis 1-phenylpropene oxides. A comparison with styrene oxide
Bellucci,Chiappe,Cordoni,Marioni
, p. 1153 - 1160 (1993)
A preferential consumption of the (1S,2S) enantiomer of (±)-trans-1-phenylpropene oxide (3) and of the (1R,2S) enantiomer of cis-1-phenylpropene oxide (5) is observed during the rabbit liver mEH catalyzed hydrolysis of these epoxides. This preference is, respectively, much lower and much higher than that found for the consumption of the (R) enantiomer in the hydrolysis of (±)-styrene oxide. These results are rationalized in terms of the K(M) and V(max) of the respective reactions.
Asymmetric Epoxidation of Olefins Catalyzed by Substituted Aminobenzimidazole Manganese Complexes Derived from L-Proline
Tian, Jing,Lin, Jin,Zhang, Jisheng,Xia, Chungu,Sun, Wei
supporting information, p. 593 - 600 (2021/11/16)
A family of manganese complexes [Mn(Rpeb)(OTf)2] (peb=1-(1-ethyl-1H-benzo[d]imidazol-2-yl)-N-((1-((1-ethyl-1H-benzo[d]imidazol-2-yl)methyl) pyrrolidin-2-yl)methyl)-N-methylmethanamine)) derived from L-proline has been synthesized and characterized, where R refers to the group at the diamine backbone. X-ray crystallographic analyses indicate that all the manganese complexes [Mn(Rpeb)(OTf)2] exhibit cis-α topology. These types of complexes are shown to catalyze the asymmetric epoxidation of olefins employing H2O2 as a terminal oxidant with up to 96% ee. Obviously, the R group of the diamine backbone can influence the catalytic activity and enantioselectivity in the asymmetric epoxidation of olefins. In particular, Mn(i-Prpeb)(OTf)2 bearing an isopropyl arm, cannot catalyze the epoxidation reaction with H2O2 as the oxidant. However, when PhI(OAc)2 is used as the oxidant instead, all the manganese complexes including Mn(i-Prpeb)(OTf)2 can promote the epoxidation reactions efficiently. Taken together, these results indicate that isopropyl substitution on the Rpeb ligand inhibits the formation of active Mn(V)-oxo species in the H2O2/carboxylic acid system via an acid-assisted pathway.
Asymmetric azidohydroxylation of styrene derivatives mediated by a biomimetic styrene monooxygenase enzymatic cascade
Franssen, Maurice C. R.,Hollmann, Frank,Martínez-Montero, Lía,Paul, Caroline E.,Süss, Philipp,Schallmey, Anett,Tischler, Dirk
, p. 5077 - 5085 (2021/08/16)
Enantioenriched azido alcohols are precursors for valuable chiral aziridines and 1,2-amino alcohols, however their chiral substituted analogues are difficult to access. We established a cascade for the asymmetric azidohydroxylation of styrene derivatives leading to chiral substituted 1,2-azido alcohols via enzymatic asymmetric epoxidation, followed by regioselective azidolysis, affording the azido alcohols with up to two contiguous stereogenic centers. A newly isolated two-component flavoprotein styrene monooxygenase StyA proved to be highly selective for epoxidation with a nicotinamide coenzyme biomimetic as a practical reductant. Coupled with azide as a nucleophile for regioselective ring opening, this chemo-enzymatic cascade produced highly enantioenriched aromatic α-azido alcohols with up to >99% conversion. A bi-enzymatic counterpart with halohydrin dehalogenase-catalyzed azidolysis afforded the alternative β-azido alcohol isomers with up to 94% diastereomeric excess. We anticipate our biocatalytic cascade to be a starting point for more practical production of these chiral compounds with two-component flavoprotein monooxygenases.
