The transition-metal catalyzed asymmetric hydrogenation of unfunctionalized alkenes is challenging. Herein, we report an efficient iridium-catalyzed asymmetric hydrogenation of unfunctionalized cycloalkenes, delivering chiral 2-aryl tetralins in excellent yields and with moderate to excellent enantioselectivities. The reaction can be performed on a gram-scale with a low catalyst loading (S/C = 1000), and the reduced product was obtained without erosion of the enantioselectivity. Deuterium experiments indicated that the C═C bond in the substrate is hydrogenated directly without isomerization.
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http://dx.doi.org/10.1021/acs.orglett.4c02054 | DOI Listing |
Nano Lett
January 2025
Zhejiang Engineering Research Center for Tissue Repair Materials and Wenzhou Key Laboratory of Biomaterials and Engineering and Wenzhou Key Laboratory of Biophysics, Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325001, China.
Saccharides and peptides with markedly disparate stereochemical features serve as pivotal chiral molecular partners in living systems. The importance of glycosylation in influencing glycopeptide self-assembly has been recognized. However, how different chiral combinations of saccharides and peptides influence the macroscopic hydrogel mechanics, fiber nanomechanics, asymmetric molecular packing, and thermodynamic changes during glycopeptide self-assembly remains unknown.
View Article and Find Full Text PDFNanotechnology
January 2025
Department of Electrical and Computer Engineering, Nazarbayev University, Nazarbayev University, Astana, Kazakhstan, Astana, 010000, KAZAKHSTAN.
Non-equilibrium molecular dynamics (NEMD) simulations reveal the existence of a spontaneous heat current (SHC) in the absence of a temperature gradient and demonstrate ultra-high thermal rectification in asymmetric trapezoid-shaped graphene. These unique properties have potential applications in power generation and thermal circuits, functioning as thermal diodes. Our findings also show the presence of negative and zero thermal conductivity in this system.
View Article and Find Full Text PDFBeilstein J Org Chem
January 2025
Department of Organic Chemistry, Faculty of Natural Science, Comenius University Bratislava, Mlynská dolina, Ilkovičova 6, 842 15 Bratislava, Slovakia.
Axial chirality is present in a variety of naturally occurring compounds, and is becoming increasingly relevant also in medicine. Many axially chiral compounds are important as catalysts in asymmetric catalysis or have chiroptical properties. This review overviews recent progress in the synthesis of axially chiral compounds via asymmetric organocatalysis.
View Article and Find Full Text PDFJ Org Chem
January 2025
Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
Dual photoredox and copper-catalyzed remote asymmetric C(sp)-H alkylation of hydroxamic acid derivatives with glycine derivatives via a 1,5-hydrogen transfer (1,5-HAT) process has been realized. The reaction was characterized by redox-neutral and mild conditions, good yields, excellent enantioselectivity, and broad substrate scope. This protocol provides a straightforward and efficient strategy to prepare highly valuable enantioenriched noncanonical α-amino acids.
View Article and Find Full Text PDFSmall
January 2025
Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou, 510006, P. R. China.
Developing efficient, multifunctional electrodes for energy storage and conversion devices is crucial. Herein, lattice strains are reported in the β-phase polymorph of CoMoO within CoMoO@CoO heterostructure via phosphorus doping (P-CoMoO@CoO) and used as a high-performance trifunctional electrode for supercapacitors (SCs), hydrogen evolution reaction (HER), and oxygen evolution reaction (OER) in alkaline electrolytes. A tensile strain of +2.
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