Results 31 to 40 of about 2,895 (193)

Chiral Phosphoric Acid Diesters as Ligands in Asymmetric Transition Metal Catalyzed Hydrogenation

CHIMIA, 2003
A chiral phosphoric acid diester, specifically the BINOL-based derivative, has been used for the first time in Rh-, Ir-, and Pd-catalyzed hydrogenation of olefins and imines, giving ee-values of up to 85%.
Manfred T. Reetz, Thorsten Sell, Richard Goddard   +2 more
doaj   +1 more source

Water, Alcohols, Amines, and Amides as Formal Hydrogen‐Atom‐Transfer Reagents Through Activation With Redox‐Active Lewis Acids

Angewandte Chemie, EarlyView.
Protic molecules containing strong O─H or N─H bonds typically resist hydrogen‐atom abstraction because of the high reactivity of the resulting heteroatom‐centered radicals. However, association of the protic molecules with redox‐active Lewis acids can provide powerful hydrogen‐atom donors or proton‐coupled‐electron‐transfer reagents.
Petra Vojáčková, Armido Studer
wiley   +2 more sources

Applications of chiral spirocyclic phosphoric acid in the synthesis of natural products [PDF]

E3S Web of Conferences, 2021
With a 10 years development, chiral spirocyclic phosphoric acids (SPAs) have attracted a substantial amount of attention from the synthetic organic chemistry community. This kind of small molecule organic catalysts has some advantages like easy to obtain,
Yang Fan
doaj   +1 more source

Development of diverse adjustable axially chiral biphenyl ligands and catalysts

iScience, 2023
Summary: Development of highly efficient and practical chiral ligands and catalysts is an eternal theme in asymmetric synthesis. Here, we report the design, synthesis, and evaluation of a new kind of adjustable axially chiral biphenyl ligands and ...
Jiyang Jie, Haijun Yang, Yufen Zhao, Hua Fu   +3 more
doaj   +1 more source

Organocatalytic asymmetric selenofunctionalization of tryptamine for the synthesis of hexahydropyrrolo[2,3-b]indole derivatives

Beilstein Journal of Organic Chemistry, 2013
A chiral phosphoric acid-catalyzed selenofunctionalization of tryptamine derivatives provides access to 3a-(phenylselenyl)-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole derivatives in high yields and with synthetically useful levels of enantioselectivity ...
Qiang Wei, Ya-Yi Wang, Yu-Liu Du, Liu-Zhu Gong   +3 more
doaj   +1 more source

Chiral Phosphoric Acid-Catalyzed Asymmetric Synthesis of Axially Chiral Arylpyrazole

Organic Letters
A chiral phosphoric acid-catalyzed efficient, operationally simple, general method for straightforward syntheses of axially chiral arylpyrazole employing 3-aryl-5-aminopyrazoles reacting with azonaphthalenes was firstly reported. A wide variety of axially chiral heterobiaryl diamines in generally good yields with excellent enantioselectivities were ...
Shi-Wu Li, Yu Qi, Shujun Tong, Jiaqi Pu
openaire   +2 more sources

Organocatalytic asymmetric synthesis of bioactive hexahydropyrrolo[2,3-b]indole-containing tetrasubstituted allenes bearing multiple chiral elements

Tetrahedron Chem, 2022
An organocatalytic asymmetric construction of hexahydropyrrolo[2,3-b]indole-containing tetrasubstituted allene scaffolds bearing both axial chirality and central chirality has been established via a cascade 1,8-addition/dearomatization-cyclization ...
Jing-Yi Wang, Shuming Zhang, Xian-Yang Yu, Yu-Hao Wang, Hong-Lin Wan, Shu Zhang, Wei Tan, Feng Shi   +7 more
doaj   +1 more source

Highly Enantioselective Hydrogenation of Enamides Catalyzed by Chiral Phosphoric Acids [PDF]

Organic Letters, 2009
A highly enantioselective hydrogenation of enamides catalyzed by a dual chiral-achiral acid system was developed. By employing a substoichiometric amount of a chiral phosphoric acid and acetic acid, catalyst loadings as low as 1 mol % of the chiral catalyst were sufficient to provide excellent yield and enantioselectivity of the reduction product.
Guilong, Li, Jon C, Antilla
openaire   +2 more sources

Atomically precise metal cluster enzymes for pathological tissue regeneration

BMEMat, EarlyView.
Schematic illustration of atomically precise metal cluster enzymes (MCEs) for pathological tissue regeneration. Atomically precise MCEs can modulate biological processes, such as attenuation of inflammatory responses, eradication of bacterial pathogens, regulation of angiogenesis, and promotion of cell development.
Ziqiang Xiong, Zhifeng Shi, Mengqing Li, Jien Han, Haoyan Chen, Maofei Ran, Shaojian Zhong, Limin Ma, Chengyun Ning, Youzhun Fan, Zhenghua Tang, Peng Yu   +11 more
wiley   +1 more source

Carbon‐Based Electrodes for Sodium‐Ion Batteries: Material Design, Electrochemical Performance, and Challenges

Carbon and Hydrogen, EarlyView.
Carbon‐based electrodes, including graphite, graphene, and CNT composites, are promising candidates for sodium‐ion batteries due to their stability, conductivity, and abundance. Their electrochemical performance, key limitations, and strategies for improving practical SIB applications are highlighted.
Talha Munir, Rizwan Asghar, Mehboob Ur Rahman, Zaima Afzal   +3 more
wiley   +1 more source