Results 71 to 80 of about 1,028 (242)

Organocatalytic Formal (3+2+1)‐Cycloaddition of Allenoates, Michael Acceptors, and Carbaldehydes

Chemistry – A European Journal, EarlyView.
The use of secondary amine Lewis base organocatalysts allows for the unprecedented activation of allenoates for formal (3+2+1)‐cycloadditions with Michael acceptors and aromatic carbaldehydes. ABSTRACT Employing secondary amines as covalently interacting Lewis basic organocatalysts allows for the activation of electron‐deficient allenes (allenoates ...
David Naderer, Alexander Pötscher, Katharina Eder, Uwe Monkowius, Markus Himmelsbach, Mario Waser   +5 more
wiley   +1 more source

Enantioselective Circular Dichroism Sensing of Cysteine and Glutathione with Gold Nanorods

, 2016
Enantioselective analysis of biological thiols, including cysteine (Cys) and glutathione (GSH), is extremely important because of their unique role in bioentities. Here we demonstrated that the end-to-end assemblies of plasmonic gold nanorods with chiral
Yuchen Li (1501165), Shaoqin Liu (1694335), Fu Zhu (1694338), Mei Yan (436085), Xinyu Li (568185)   +4 more
core   +2 more sources

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

Classification and Identification of Perfume Scents by an Enantioselective Colorimetric Sensor Array of Chiral Metal‐Organic‐Framework‐Based Fabry‐Pérot Films

Many odors, like perfumes, are complex mixtures of chiral and achiral molecules where the cost-efficient (enantio−)selective sensing represents a major technical challenge.
Zhan, Kuo, Heinke, Lars, Kanj, Anemar Bruno   +2 more
core   +1 more source

Enantioselective Recognition of α-Hydroxycarboxylic Acids and N-Boc-Amino Acids by Counterion-Displacement Assays with a Chiral Nickel(II) Complex

, 2016
A new chiral sensor based on an N,N′-dioxide nickel(II) complex was prepared, which could visually recognize a series of chiral α-hydroxycarboxylic acid enantiomers by coordination and self-assembly forming into nanospheres or nanofibers.
Wentao Wang (120529), Xuan He (281431), Xiaohua Liu (593781), Lili Lin (451927), Xiaoming Feng (332783), Qi Zhang (28502)   +5 more
core   +1 more source

Nitrooxylation in Organic Synthesis: From Classical Nitrate Ester Formation to Modern Catalytic Strategies

Chemistry – A European Journal, EarlyView.
Nitrooxylation—the installation of nitrate esters (–ONO2) has evolved from classical mixed‐acid protocols to catalytic and mechano‐, flow‐, photo‐, and electrochemical strategies. This review delineates ionic and radical manifolds for C–ONO2 bond formation, emphasizing mechanistic control, selected substrate scope, and selectivity.
Jayanta Dey, Dmitry Katayev
wiley   +1 more source

Next‐Generation Carbon‐Based Anodes for Alkali Metal‐Ion Batteries: Recent Progress on Biphenylene and Emerging Materials

ENERGY &ENVIRONMENTAL MATERIALS, EarlyView.
Recent advances in carbon‐based anodes for alkali metal‐ion batteries are critically reviewed, with emphasis on biphenylene and other emerging carbon allotropes. Biphenylene exhibits exceptional theoretical electrochemical properties beyond conventional graphite, highlighting its strong potential as a next‐generation anode material once scalable ...
Adewale Hammed Pasanaje, Nirpendra Singh
wiley   +1 more source

Synthesis of 2‐Aza‐Bicyclo[4.3.0]nonane Derivatives Related to the Camporidines via Intramolecular [3+2]‐Cycloaddition

European Journal of Organic Chemistry, EarlyView.
The intramolecular nitrile oxide olefin [3 + 2]‐cycloaddition offers a reliable entry toward 2‐aza‐bicyclo[4.3.0]‐nonanes, a substructure found in several bioactive piperidine alkaloids. The required oxime precursors were prepared in non‐racemic form by Ir‐catalyzed asymmetric allylation and ring‐closing metathesis.
Alicia Köcher, Tobias Wilczek, Nora Katharina Korber, Jörg-Martin Neudörfl, Bernd Goldfuss, Hans-Günther Schmalz   +5 more
wiley   +1 more source

A development of a molecularly imprinted polymer: Specific for ochratoxin A: Theoretical and sensor applications

, 2004
In this work the development of two molecularly imprinted polymers, specific for ochratoxin A, is presented. Ochratoxin A is produced by several Aspergillus and Penicillium species and is common in cereals and other starch rich foods and has also been
Turner, Nicholas W.
core  

Isotellurourea‐Catalyzed Enantioselective (4+2)‐Heterocycloadditions of But‐2‐ynoates and Michael Acceptors

European Journal of Organic Chemistry, EarlyView.
Isotelluroureas allow for the use of alkynoates for asymmetric (4+2)‐heterocycloadditions with different Michael acceptors. Alk‐2‐ynoates are readily available starting materials which, in principle, can be utilized for cycloadditions in analogy to structurally similar allenoates.
Anna Scheucher, Mario Waser
wiley   +1 more source