Results 91 to 100 of about 511,953 (205)

Stereochemical Control in the Matteson Reaction

Chemistry – A European Journal, EarlyView.
The Matteson homologation is a highly versatile method for the stereoselective insertion of carbenoids into boronic esters. Through iterative application of the process, complex chiral molecules can be synthesized. The stereoselectivity of the reaction is determined by a chiral diol incorporated in the boronic ester.
Hae Mo Lee, Christoph Hirschhäuser
wiley   +1 more source

Resolution, quantification, and reliable determination of enantiomeric excess of proteinogenic and non-proteinogenic amino acids by comprehensive two-dimensional gas chromatography. [PDF]

J Sep Sci, 2022
Pepino R, Leyva V, Garcia AD, Bocková J, Meinert C.   +4 more
europepmc   +1 more source

Cyclopropylamine‐Derived Distonic Iminium Radicals: Photoinduced Strategies in Chemo‐ and Stereo‐Selective Synthesis

Chemistry – A European Journal, EarlyView.
Cyclopropylamines have emerged as powerful photocatalytic building blocks. Upon light‐induced single‐electron oxidation, they undergo strain‐release ring opening to generate distonic iminium radicals that enable diverse transformations, including ring‐opening functionalization, formal [3 + 2] cycloadditions, radical cascades, and asymmetric bond ...
Maria Chiara Cabua, Alberto Luridiana, Francesco Secci, Emanuele Cocco   +3 more
wiley   +1 more source

Bipolar Electrochemical Measurement of Enantiomeric Excess with Inherently Chiral Polymer Actuators. [PDF]

ACS Meas Sci Au, 2021
Arnaboldi S, Salinas G, Bonetti G, Cirilli R, Benincori T, Kuhn A.   +5 more
europepmc   +1 more source

Regioselective Aldol Reactions Directed by Charge and Orbital Effects in Cyclic Germyl Dienolates: Synthesis of Three Distinct Regio‐ and Stereoisomers

Chemistry – A European Journal, EarlyView.
Charge and orbital control represent fundamental principles in organic chemistry. In this study, these principles are applied to the aldol reactions of a cyclic Ge‐dienolate. By systematically tuning the charge and orbital distributions of the Ge‐dienolates and their aldehyde reaction partners, regio‐ and stereoselective access to three distinct aldol ...
Taishi Nojima, Akihito Konishi, Makoto Yasuda   +2 more
wiley   +1 more source

Helical springs as a color indicator for determining chirality and enantiomeric excess. [PDF]

Sci Adv, 2021
Maeda K, Hirose D, Nozaki M, Shimizu Y, Mori T, Yamanaka K, Ogino K, Nishimura T, Taniguchi T, Moro M, Yashima E.   +10 more
europepmc   +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

A Racemic Naphthyl-Coumarin-Based Probe for Quantitative Enantiomeric Excess Analysis of Amino Acids and Enantioselective Sensing of Amines and Amino Alcohols. [PDF]

ChemistryOpen, 2022
Li JY, Wang L, Yin LP, Jiang XM, Guo K, Zhang C, Yu SS, Yu XQ, Wang Q.   +8 more
europepmc   +1 more source

Synthesis and Structures of Novel Chiral Cyclic Hypervalent Iodine(III) Reagents for Metal‐Free Ligand‐Transfer Reactions

Chemistry – A European Journal, EarlyView.
Several new chiral cyclic hypervalent iodine(III) reagents have been synthesized and characterized. Carbon‐based ligands were successfully installed onto the hypervalent iodine centers, giving thus access to novel chiral cyano‐, trifluoromethyl‐ or alkynyl‐bearing λ3‐iodanes.
Emmanuel Valzer, Jean‐Marc Sotiropoulos, Karinne Miqueu, Laurent Pouységu, Stéphane Quideau   +4 more
wiley   +1 more source

Mirror image hydrocarbons from Tropical and Boreal forests [PDF]

Atmospheric Chemistry and Physics, 2007
Monoterpenes, emitted in large quantities by trees to attract pollinators and repel herbivores, can exist in mirror image forms called enantiomers. In this study such enantiomeric pairs have been measured in ambient air over extensive forest ecosystems ...
J. Williams, N. Yassaa, S. Bartenbach, J. Lelieveld   +3 more
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