Mechanism of Palladium‐Catalyzed Spiroannulation of Naphthols with Alkynes: A Density Functional Theory Study
Sign Up to like & getrecommendations! Published in 2020 at "ChemCatChem"
DOI: 10.1002/cctc.202000613
Abstract: Pd‐catalyzed spiroannulation of bromophenylnaphthalenols with acetylenes to achieve asymmetric dearomatization is a powerful way to construct chiral spiro‐compounds. DFT calculations with the M06 functional have been performed to reveal the mechanism and enantioselectivity of this… read more here.
Keywords: enantioselectivity; mechanism palladium; spiroannulation; catalyzed spiroannulation ... See more keywords
Significant improvement of the enantioselectivity of a halohydrin dehalogenase for asymmetric epoxide ring opening reactions by protein engineering
Sign Up to like & getrecommendations! Published in 2020 at "Applied Microbiology and Biotechnology"
DOI: 10.1007/s00253-020-10356-x
Abstract: Halohydrin dehalogenases (HHDHs) have attracted much attention due to their ability to synthesize enantiomerically enriched epoxides and β-haloalcohols. However, most of the HHDHs exhibit low enantioselectivity. Here, a HHDH from the alphaproteobacteria isolate 46_93_T64 (… read more here.
Keywords: enantioselectivity; protein engineering; significant improvement; halohydrin ... See more keywords
Heterogeneous Enantioselective Hydrogenation of Aromatic Ketones Catalyzed by Rh Nanoparticles Immobilized in Ionic Liquid
Sign Up to like & getrecommendations! Published in 2019 at "Catalysis Letters"
DOI: 10.1007/s10562-019-02768-w
Abstract: Rhodium nanoparticles (Rh NPs) stabilized by natural cinchona alkaloids were synthesized in imidazolium-based ionic liquids using H2 as the reductant. Characterization showed well-dispersed Rh NPs of about 1.96 nm (TEM and HRTEM) and confirmed the ionic… read more here.
Keywords: enantioselectivity; ionic liquid; chemoselectivity; hydrogenation ... See more keywords
Enhancing enantioselectivity of Candida antarctica lipase B towards chiral sec-alcohols bearing small substituents through hijacking sequence of A homolog
Sign Up to like & getrecommendations! Published in 2021 at "Tetrahedron Letters"
DOI: 10.1016/j.tetlet.2021.153186
Abstract: Abstract Candida antarctica lipase B (CAL-B) exhibits extraordinary enantioselectivity towards most chiral sec-alcohols but not towards sec-alcohols bearing substituents smaller than a propyl group (i.e., (±)-but-3-yn-2-ol (E = 4) and (±)-butan-2-ol (E = 7)). Previously, we reported a homologous… read more here.
Keywords: enantioselectivity; sec alcohols; candida antarctica; lipase ... See more keywords
Highly Efficient Asymmetric Hydrogenation Catalyzed by Iridium Complexes with Tridentate Chiral Spiro Aminophosphine Ligands.
Sign Up to like & getrecommendations! Published in 2023 at "Accounts of chemical research"
DOI: 10.1021/acs.accounts.2c00764
Abstract: ConspectusCatalytic asymmetric hydrogenation is one of the most reliable, powerful, and environmentally benign methods for the synthesis of chiral molecules with high atom economy and has been successfully applied in the industrial production of pharmaceuticals,… read more here.
Keywords: enantioselectivity; hydrogenation; iridium; asymmetric hydrogenation ... See more keywords
Molybdenum-Catalyzed Enantioselective Synthesis of Planar-Chiral (η5-Phosphacyclopentadienyl)manganese(I) Complexes and Application in Asymmetric Catalysis
Sign Up to like & getrecommendations! Published in 2017 at "Organometallics"
DOI: 10.1021/acs.organomet.7b00704
Abstract: Enantioselective desymmetrization of Cs-symmetric (η5-2,5-dialkenylphospholyl)(allyldiphenylphosphine)manganese(I) dicarbonyl complexes 1 was realized by molybdenum-catalyzed asymmetric ring-closing metathesis (ARCM), and the corresponding bridged planar-chiral phosphacymantrene derivatives 2 were obtained in good yields with excellent enantioselectivity. The enantioselectivity of… read more here.
Keywords: enantioselectivity; molybdenum catalyzed; catalyzed enantioselective; planar chiral ... See more keywords
Optimizing the Local Chemical Environment on a Bifunctional Helical Peptide Scaffold Enables Enhanced Enantioselectivity and Cooperative Catalysis.
Sign Up to like & getrecommendations! Published in 2022 at "Organic letters"
DOI: 10.1021/acs.orglett.2c00857
Abstract: We describe a proof-of-concept study in which peptide-bound enamine and thiourea catalysts are used to facilitate the conjugate addition of cyclohexanone to nitroolefins. Our bifunctional peptide scaffold is modified to optimize the local environment around… read more here.
Keywords: catalysis; enantioselectivity; environment; peptide ... See more keywords
Discovery and Structural Analysis to Improve the Enantioselectivity of Hydroxynitrile Lyase from Parafontaria laminata Millipedes for (R)-2-Chloromandelonitrile Synthesis
Sign Up to like & getrecommendations! Published in 2020 at "ACS Omega"
DOI: 10.1021/acsomega.0c03070
Abstract: Hydroxynitrile lyase (HNL) catalyzes the reversible synthesis and degradation of cyanohydrins, which are important synthetic intermediates for fine chemical and pharmaceutical industries. Here, we report the discovery of HNL from Parafontaria laminata (PlamHNL) millipedes, purification… read more here.
Keywords: parafontaria laminata; enantioselectivity; hydroxynitrile lyase; hnl ... See more keywords
Effect of Propargylic Substituents on Enantioselectivity and Reactivity in Ruthenium-Catalyzed Propargylic Substitution Reactions: A DFT Study
Sign Up to like & getrecommendations! Published in 2022 at "ACS Omega"
DOI: 10.1021/acsomega.2c04645
Abstract: We recently proposed a transition-state model for asymmetric propargylic substitution reactions of propargylic alcohols catalyzed by optically active thiolate-bridged diruthenium complexes [Chem. – Asian J.2021, 16, 3760−376634549529]. In the present study, we further examined the… read more here.
Keywords: enantioselectivity; substitution; propargylic substitution; group ... See more keywords
C-N Bond Forming Radical Rebound Is the Enantioselectivity-Determining Step in P411-Catalyzed Enantioselective C(sp3)-H Amination: A Combined Computational and Experimental Investigation.
Sign Up to like & getrecommendations! Published in 2022 at "Journal of the American Chemical Society"
DOI: 10.1021/jacs.2c02283
Abstract: Engineered metalloenzymes represent promising catalysts for stereoselective C-H functionalization reactions. Recently, P450 enzymes have been evolved to allow for new-to-nature intramolecular C(sp3)-H amination reactions via a nitrene transfer mechanism, giving rise to diamine derivatives with… read more here.
Keywords: enantioselectivity; step; radical rebound; sp3 ... See more keywords
Engineered P450 Atom-Transfer Radical Cyclases are Bifunctional Biocatalysts: Reaction Mechanism and Origin of Enantioselectivity.
Sign Up to like & getrecommendations! Published in 2022 at "Journal of the American Chemical Society"
DOI: 10.1021/jacs.2c04937
Abstract: New-to-nature radical biocatalysis has recently emerged as a powerful strategy to tame fleeting open-shell intermediates for stereoselective transformations. In 2021, we introduced a novel metalloredox biocatalysis strategy that leverages the innate redox properties of the… read more here.
Keywords: transfer radical; enantioselectivity; atom transfer; mechanism ... See more keywords