Results 41 to 50 of about 4,429,443 (158)

Stereoretentive Nucleophilic Aromatic Substitution Accesses Atropisomeric 4‐Amino‐N‐Arylquinolinium Salts

Chemistry – A European Journal, EarlyView.
Quinolin‐4‐ones were converted to chloroquinolinium salts, allowing formation of axially chiral aminoquinolinium salts via an enantioretentive SNAr reaction with a variety of amine nucleophiles. The salts have a high rotational barrier, with a racemization half‐life of ∼1000s of years.
Darren Holmes, Nia Foster, Saima Ansari, Paul Kavanagh, Paul Dingwall, Peter C. Knipe   +5 more
wiley   +1 more source

Chiral Pyrazolinylidene Complexes for Asymmetric Catalysis

Chemistry – A European Journal, EarlyView.
The synthesis and application of pyrazolin‐5‐ylidene NHC chiral‐at‐ruthenium catalysts is reported. The strong donating pyrazolin‐5‐ylidene ligands led to highly electron rich ruthenium complexes, which showed excellent catalytic activity and enantioselectivity in the intramolecular aziridination of an alkene.
Felix Möller, Nemrud Demirel, Thomas Krüger, Linus Plohnke, Jennifer Schröder, Sergei I. Ivlev, Eric Meggers   +6 more
wiley   +1 more source

Rhodium‐Catalyzed Synthesis of Enantioenriched α‐Substituted Primary Amines Through Asymmetric Transfer Hydrogenation

Chemistry – A European Journal, EarlyView.
Enantioenriched α‐substituted primary amines are efficiently prepared by rhodium‐catalyzed asymmetric transfer hydrogenation of ortho‐hydroxyaryl N─H imines under mild conditions using a low catalyst loading and ammonium formate as the hydrogen source in high yields (up to 99%) and enantioselectivities (up to 99% ee).
Chonghuo Liu, Guillaume Lefèvre, Qin Yin, Phannarath Phansavath, Virginie Ratovelomanana‐Vidal   +4 more
wiley   +1 more source

Studies of hexahelicene bonded phases for the HPLC resolution of enantiomers [PDF]

The thesis presents a review of the literature on the HPLC resolution of enantiomers using chiral stationary phases and discusses the mechanisms of separation and the utility of these phases.
Del Alamo, Aurora
core  

Formation of bioinorganic complexes by the corrosive adsorption of (S)-proline on Ni/Au(111) [PDF]

, 2015
R.T.S.G. and J.G. acknowledge the Engineering and Physical Sciences Research Council (EPSRC, UK) for the award of a PhD studentship. The research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/
Baddeley, Christopher John, Gano, Jerome E., Greenwood, John, Grillo, Federico, Fruchtl, Herbert Anton, Lacovig, Paolo, Simpson, Grant James, Francis, Stephen Malcolm, Gano, Jerome E., Green, Riho Thomas Seljamae, Schaub, Renald   +10 more
core   +1 more source

Exploring the Boundaries of Aromaticity in Complex Structures and Excited States Through Computational Analysis

Chemistry – A European Journal, EarlyView.
Understanding aromaticity has evolved from benzene‐centric concepts to a broad multidimensional framework spanning organic, inorganic, and excited‐state systems. This review highlights ambiguities between magnetic, electronic, geometric, and energetic descriptors, emphasizing the need for unified, multi‐criteria approaches.
Sílvia Escayola, Miquel Solà, Albert Poater   +2 more
wiley   +1 more source

Comparison of various chiral stationary phases for the chromatographic separation of chiral pharmaceuticals [PDF]

, 2009
Many pharmaceuticals contain active ingredients that have more than one stereoisomer. An important concern is the recognition that these different stereoisomers do not necessarily have identical, or even desirable biological activity.
Layton, Sherry E., NC DOCKS at The University of North Carolina Wilmington   +1 more
core  

Generalized Beth–Uhlenbeck Entropy Formula From the Φ‐Derivable Approach

Contributions to Plasma Physics, EarlyView.
ABSTRACT We derive a generalized Beth–Uhlenbeck formula for the entropy of a dense fermion system with strong two‐particle correlations, including scattering states and bound states. We work within the Φ‐derivable approach to the thermodynamic potential.
David Blaschke, Gerd Röpke, Gordon Baym
wiley   +1 more source

Investigation of Novel Peptide Chiral Selectors Prepared by Solid-Phase Synthesis with a tert-Butoxycarbonyl Amino Acid [PDF]

, 2009
A new class of chiral stationary phases (CSP) with peptide chiral selectors was prepared by solid-phase synthesis with a tert-butoxycarbonyl-L-amino acid on silica. The type of amino acid that is favorable for this class of CSP is discussed.
Ohba, Yoshihito, Kuroda, Naotaka, Arakawa, Miyuki, Ohyama, Kaname, Kamino, Masahiro, Wada, Mitsuhiro, Nakashima, Kenichiro, Oyamada, Kana, Kishikawa, Naoya   +8 more
core   +1 more source

Chiral HPLC Separation of Phosphonothrixin and Phosphonate Derivatives and Electronic Circular Dichroism Characterization of the Isolated Enantiomers. [PDF]

Electrophoresis
Natural compound phosphonothrixin's herbicidal activity resides exclusively in its (S)‐enantiomer, yet existing enantioselective syntheses are cumbersome, and direct chiral LC separation is hampered by the compound's high polarity, lack of aromatic groups, and metal chelation–induced peak tailing.
Maalouf M, Knab M, Gessner L, Engelhardt M, Friedrich S, Gross H, Boeckler F, Hughes CC, Lämmerhofer M.   +8 more
europepmc   +2 more sources