Results 111 to 120 of about 10,956 (235)
ChemCatChem, Accepted Article.The activation of electron poor allenes with Lewis base catalysts allows for unique transformations and chiral isochalcogenoureas were recently introduced as powerful catalysts for allenoate‐based (4+2)‐cycloadditions. We herein now report the use of these catalysts for the activation and control of allenylsulfones and propargylsulfones for asymmetric (
Mario Hofer +3 more
wiley +1 more source
ChemistryEurope, EarlyView.The first report on zinc‐catalyzed enantioselective alkylation of aldehydes mediated by a chiral auxiliary is revisited, and the studies show much more complex behavior than previously thought. Studies show an enantiodivergence of the reaction as a function of its progress, due to an autoinduction phenomenon.
Joseph El Khoury +3 more
wiley +1 more source
The Emergence of Quinone Methides in Asymmetric Organocatalysis
Molecules, 2015 Quinone methides (QMs) are highly reactive compounds that have been defined as “elusive” intermediates, or even as a “synthetic enigma” in organic chemistry.
Lorenzo Caruana +2 more
doaj +1 more source
N-Heterocyclic Carbenes Supported on Vinylic Addition Polynorbornene: A Recyclable and Recoverable Organocatalyst [PDF]
, 2014 Producción CientíficaA bromoalkyl functionalized vinylic addition polynorbornene has been used as an inert new scaffold to support imidazolium salts by straightforward nucleophilic substitution using different imidazoles ImR (R=Me, mesityl, 2,6-iPr2C6H3).
Albéniz Jiménez, Ana Carmen +1 more
core +3 more sources
Organocatalyzed Diels‐Alder Reactions: Unexplored Hydrogen Bond Donor Catalysts
ChemPlusChem, EarlyView.Quantum chemical activation strain analyses show that urea‐derived hydrogen‐bond organocatalysts, including unconventional alternatives to the C=O group (e. g., C=C and C=Si), lower the Diels‐Alder reaction barrier between butadiene and acrolein by Pauli lowering catalysis.
Eveline H. Tiekink +3 more
wiley +1 more source
Beilstein Journal of Organic Chemistry, 2016 Hydrogen bond donor catalysis represents a rapidly growing subfield of organocatalysis. While traditional hydrogen bond donors containing N–H and O–H moieties have been effectively used for electrophile activation, activation based on other types of non ...
Pavel Nagorny, Zhankui Sun
doaj +1 more source
Recent advances in catalysis using transition metals-bounding organic ligands assisted by ultrasound and/or microwave [PDF]
, 2015 Usually, in organic and organometallic synthesis an external conventional heat source is applied to carry out a chemical reaction at high temperature. Nonetheless, these conventional heating systems have some disadvantages as the heterogeneous heating ...
Domini, Claudia Elizabeth +2 more
core +1 more source
Learning Strategies from Nature's Blueprint to Cyclic Carbonate Synthesis
ChemSusChem, Volume 18, Issue 6, March 15, 2025.The development of sustainable synthetic methods for cyclic carbonates draws inspiration from nature, focusing on eco‐friendly processes and renewable resources like CO2 and biomass. This review explore various CO2 activation mechanisms, green chemistry principles, and green catalysts.
Erika Saccullo +4 more
wiley +1 more source
Asymmetric vinylogous Mukaiyama aldol reaction of isatins under bifunctional organocatalysis: Enantioselective synthesis of substituted 3-hydroxy-2-oxindoles [PDF]
, 2018 A highly enantioselective organocatalytic vinylogous Mukaiyama aldol reaction of silyloxy dienes and isatins under bifunctional organocatalysis is presented. Substituted 3-hydroxy-2-oxindoles are synthesised in good yields and enantioselectivities. These
Alemán, José +3 more
core +2 more sources
En Route Toward Sustainable Polycarbonates Via Large Cyclic Carbonates
ChemSusChem, Accepted Article.This review reports an up‐to‐date overview of the synthetic methodologies developed for the preparation of large cyclic organic carbonates with ≥ 6‐membered rings (6M‐CCs and above), highlighting the most sustainable synthetic pathways employing diols (including renewable‐based ones) and non‐hazardous carbonyl sources, e.g., linear organic carbonates ...
Francesco Della Monica +5 more
wiley +1 more source