Results 111 to 120 of about 17,233 (279)

Flipping the Card With Enantiodivergent Organocatalysis

open access: yesChemistry – A European Journal, EarlyView.
This minireview elaborates on recent organocatalytic strategies for achieving enantiodivergence—the ability to access both product enantiomers using a single chiral catalyst. It highlights how achiral stimuli, such as solvent polarity and chemical additives, along with minimal catalyst modifications, trigger stereochemical inversions in reactions ...
Debora Iapadre   +3 more
wiley   +1 more source

Titanium‐Catalyzed Diastereoselective Keto‐ and Iminonitrile Cyclizations

open access: yesChemistry – A European Journal, EarlyView.
The titanium(III)‐catalyzed diastereoselective cyclization of readily‐available substituted ketonitriles gives cyclopentanones in good yield and stereoselectivity. Subsequent 1,2‐addition allows the preparation of cyclopentyls with three consecutive stereocenters.
Christoph Kern   +4 more
wiley   +1 more source

EFSA Scientific Opinion on Flavouring Group Evaluation 87 Revision 1 (FGE.87Rev1): Consideration of bicyclic secondary alcohols, ketones and related esters evaluated by JECFA (63rd meeting) structurally related to bicyclic secondary alcohols, ketones and related esters evaluated by EFSA in FGE.47 (2008) [PDF]

open access: yes, 2012
The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to consider evaluations of flavouring substances assessed since 2000 by the Joint FAO/WHO Expert Committee on Food Additives (the JECFA), and to decide whether further evaluation is necessary, as laid down in Commission ...
openaire  

Fourier Transform Infrared Spectroscopy characterization of aging-related properties of original and nano-modified asphalt binders

open access: yes, 2015
The objective of this study is to analyze the effect of aging on asphalt binders under the conditions of dry and sufficient oxygen, and to identify the functional groups related to the fatigue and rutting of asphalt mixtures.
You, Zhanping   +5 more
core   +1 more source

Oxidative Generation and Reactivity of the Cyclopropyl Radical From a Martin Silicate

open access: yesChemistry – A European Journal, EarlyView.
A photoredox strategy employing Martin silicates enables the oxidative generation and controlled capture of cyclopropyl radicals, including the naked one, long considered challenging intermediates. The method affords functionalized cyclopropanes through both Giese‐type additions and dual nickel/photoredox C(sp3)−C(sp2) cross‐couplings.
Amal Lakhal   +3 more
wiley   +1 more source

Oxyanion and tetrahedral intermediate stabilization by subtilisin : detection of a new tetrahedral adduct

open access: yes, 2009
The peptide-derived glyoxal inhibitor Z-Ala-Ala-Phe-glyoxal has been shown to be ~10 fold more effective as an inhibitor of subtilisin than Z-Ala-Pro-Phe-glyoxal. Signals at 107.2 p.p.m. and 200.5 p.p.m.
Rogers, Louis   +3 more
core   +1 more source

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

open access: yesChemistry – 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

Elucidating metabolic and flavor evolution in traditional Chinese soy sauce during industrial-scale fermentation: A multi-omics approach

open access: yesFood Chemistry: X
The dynamic changes in metabolomics and flavoromics during the industrial-scale fermentation of Chinese traditional soy sauce were evaluated. The results revealed that the amino acid nitrogen content gradually increased to 1.03 g/100 mL after 60 days of ...
Yong-Qi Luo   +5 more
doaj   +1 more source

Hydroprocessing of synthetic kerosene over a non‐sulphided Ni/Al2O3 catalyst: Impact of alcohols and ketones on alkene conversion

open access: yesThe Canadian Journal of Chemical Engineering, EarlyView.
Abstract Synthetic jet fuel containing non‐petroleum‐derived kerosene can be produced from synthetic kerosene obtained through processes that include a hydroprocessing step. The potential use of non‐sulphided (reduced) nickel supported on alumina (Ni/Al2O3) was evaluated as an alternative to sulphided catalysts to saturate alkenes in sulphur‐free ...
Garima Chauhan   +3 more
wiley   +1 more source

Microwave‐assisted catalytic pyrolysis of textile wastes: Synergistic effects and product characteristics

open access: yesThe Canadian Journal of Chemical Engineering, EarlyView.
Abstract This study examines the microwave‐assisted catalytic pyrolysis (MACP) of individual and blended textiles (cotton, polyester, nylon 6) using ZnO and a ZnO/natural zeolite catalyst. In a custom‐built microwave reactor operated at 500°C, 1 kW power, and a 15‐min residence time, textile wastes were pyrolyzed.
Peyman Alizadeh   +3 more
wiley   +1 more source

Home - About - Disclaimer - Privacy