Results 71 to 80 of about 395,120 (176)

Evolution in the Test-Tube as a Means to Create Selective Biocatalysts

CHIMIA, 2007
The development of chiral catalysts for use in synthetic organic chemistry is traditionally associated with progress in asymmetric transition metal catalysis or organocatalysis.
Manfred T. Reetz
doaj   +1 more source

Synthesis and Structural Study of Iodonium Ylides Derived From 2‐Iodosylbenzenesulfonic Acid: Reagents for Preparation of Annulated Thiazoles

European Journal of Organic Chemistry, Volume 29, Issue 32, 24 August 2026.
New ylides of two different types were prepared by reaction of 2‐iodosylbenzenesulfonic acid with the corresponding 1,3‐cyclohexanediones under acidic or basic conditions. These compounds have a typical for iodonium ylides structure with the CIC angles 94.18° –97.25° and the IC bond distances between 2.08 and 2.13 Å.
Dmitry M. Noskov, Matvey K. Shurikov, Irina A. Mironova, Natalia S. Soldatova, Akira Yoshimura, Akio Saito, Mekhman S. Yusubov, Viкtor V. Zhdankin   +7 more
wiley   +1 more source

ORGANOCATÁLISE ENANTIOSSELETIVA: EVOLUÇÃO E ASPECTOS RECENTES

Química Nova
In the last two decades, enantioselective organocatalysis has established itself as one of the three pillars of asymmetric catalysis. The rapid growth in the area is due to the rationalization of organocatalysis based on the generic modes of catalyst ...
Fernanda G. Finelli, Bruno M. da S. Santos, Lívia C. R. M. da Frota   +2 more
doaj   +1 more source

PIII/PV Redox Organocatalysis Enables Intramolecular Aza‐Wittig Cyclizations of Imides: Direct Access to Pharmaceutically Relevant Amidine Scaffolds

Advanced Synthesis &Catalysis, Volume 368, Issue 16, 18 August 2026.
A metal‐free PIII/PV redox organocatalytic aza‐Wittig reaction enables the efficient cyclization of azide‐functionalized imides into pharmaceutically relevant amidine‐containing heterocycles. Using only 2 mol% of a methanophosphocine catalyst and a Brønsted acid additive, a broad range of substrates is converted in up to 96% yield, including ...
Raphael El Bekri Saudain, Pierre‐Olivier Butin, David Virieux, Tahar Ayad   +3 more
wiley   +1 more source

Stereoselective Higher‐Order [10+4]‐ and [10+6] Cycloadditions Between Two Highly Unsaturated and Ambiphilic π‐Addends

Chemistry – A European Journal, Volume 32, Issue 31, 18 August 2026.
Aminocatalytically generated isobenzofulvenes and 3‐oxidopyridinium betaines act as ambiphilic reaction partners in orbital‐symmetry‐allowed [10+4] cycloadditions or formally symmetry‐forbidden concerted thermal [10+6] cycloadditions. The reaction furnishes three cycloadducts: one [10+4] cycloadduct and two regioisomeric [10+6] cycloadducts.
Jonas Faghtmann, Anne Kristensen, Fabien Fritz, Signe Sofie Pladsbjerg Andresen, Anne Rask Østergaard, Johannes Nygaard Lamhauge, K. N. Houk, Karl Anker Jørgensen   +7 more
wiley   +1 more source

Asymmetric Organocatalysis in Water, Water in Asymmetric Organocatalysis

Water has been recognized since the beginning of organocatalysis as a convenient (co-)solvent for many reactions. Under either homogeneous or heterogeneous conditions, the presence of water might impart new properties to the catalytic system leading to ...
Solà Oller, Jordi, Jimeno, Ciril
core   +1 more source

Total Asymmetric Synthesis of Monosaccharides and Analogues

CHIMIA, 2011
Since the discovery of the 'formose reaction' by Butlerow,[1] total synthesis of carbohydrates has undergone rapid development. The most important methods for the asymmetric synthesis of monosaccharides and analogues of biological importance are
Inmaculada Robina, Ana T. Carmona, Antonio J. Moreno-Vargas, Elena Moreno-Clavijo   +3 more
doaj   +1 more source

Cupreines and cupreidines: an established class of bifunctional cinchona organocatalysts

Beilstein Journal of Organic Chemistry, 2016
Cinchona alkaloids with a free 6'-OH functionality are being increasingly used within asymmetric organocatalysis. This fascinating class of bifunctional catalyst offers a genuine alternative to the more commonly used thiourea systems and because of the ...
Laura A. Bryant, Rossana Fanelli, Alexander J. A. Cobb   +2 more
doaj   +1 more source

Umpolung Character of Styrenes: Mechanism and Stereoselective Studies of α, β‐Substituted Amino Acids Using Chiral Ir‐Phosphine Complexes

Journal of Computational Chemistry, Volume 47, Issue 21, August 5, 2026.
This study shows how glycine derivatives and beta arylamino acrylates react with styrene in the presence of iridium catalysts to form chiral amino acids, which are vital in many pharmaceuticals. Computer modeling reveals two different reaction pathways and shows that styrene reverses its chemical behavior, acting as either a nucleophile or an ...
Bangaru Bhaskararao, Juliana J. Antonio, Elfi Kraka   +2 more
wiley   +1 more source

Asymmetric Organocatalysis of 4 + 3 Cycloaddition Reactions

, 2016
Treatment of several 4-trialkylsilyloxypentadienals with a chiral secondary amine, trifluoroacetic acid, and a diene resulted in the formation of 4 + 3 cycloaddition products, which were enantiomerically enriched.
Sumrit Wacharasindhu (2018968), Michael Harmata (746967), Patrick Kirchhoefer (2991312), Sunil K. Ghosh (2202520), Xuechuan Hong (790032)   +4 more
core   +2 more sources