Search results for "Alcohol"
showing 10 items of 1798 documents
Asymmetric Synthesis of Monofluorinated 1-Amino-1,2-dihydronaphthalene and 1,3-Amino Alcohol Derivatives.
2016
Enantioenriched 1-amino-4-fluoro-1,2-dihydronaphthalene derivatives are accessed via two complementary synthetic strategies. The careful optimization of the reaction conditions required for the elimination step in one route has allowed both the identification of an anchimerically assisted reaction pathway and, more importantly, access to a divergent reaction pathway toward fluorinated 1,3-amino alcohols from a common intermediate just by adjusting the number of equivalents of base used.
ChemInform Abstract: Asymmetric Synthesis of Monofluorinated 1-Amino-1,2-dihydronaphthalene and 1,3-Amino Alcohol Derivatives.
2016
Enantioenriched 1-amino-4-fluoro-1,2-dihydronaphthalene derivatives are accessed via two complementary synthetic strategies. The careful optimization of the reaction conditions required for the elimination step in one route has allowed both the identification of an anchimerically assisted reaction pathway and, more importantly, access to a divergent reaction pathway toward fluorinated 1,3-amino alcohols from a common intermediate just by adjusting the number of equivalents of base used.
Benzyl alcohol to benzaldehyde oxidation on MnOx clusters: Unraveling atomistic features
2021
Abstract The catalytic oxidation of benzyl alcohol with O 2 is a promising option for the production of benzaldehyde, from both environmental and economical viewpoints. In particular, highly dispersed MnO x systems feature good activity and selectivity in a wide range of temperatures, although deactivation phenomena by over-oxidation and/or poisoning of active sites are generally recorded. On this account, a density functional theory study was performed on cluster-sized catalyst models, namely Mn 4 O 8 and over-oxygenated Mn 4 O 9 fragments, to predict the reactivity pattern of MnO x catalysts in the selective aerobic oxidation of benzyl alcohol. Several pathways concur to determine the who…
Oxygen-assisted hydroxymatairesinol dehydrogenation: a selective secondary-alcohol oxidation over a gold catalyst.
2013
Selective dehydrogenation of the biomass-derived lignan hydroxymatairesinol (HMR) to oxomatairesinol (oxoMAT) was studied over an Au/Al(2)O(3) catalyst. The reaction was carried out in a semi-batch glass reactor at 343 K under two different gas atmospheres, namely produced through synthetic air or nitrogen. The studied reaction is, in fact, an example of secondary-alcohol oxidation over an Au catalyst. Thus, the investigated reaction mechanism of HMR oxidative dehydrogenation is useful for the fundamental understanding of other secondary-alcohol dehydrogenation over Au surfaces. To investigate the elementary catalytic steps ruling both oxygen-free- and oxygen-assisted dehydrogenation of HMR…
Metal- and Reagent-Free Electrochemical Synthesis of Alkyl Arylsulfonates in a Multi-Component Reaction.
2020
Abstract This work presents the first electrochemical preparation of alkyl arylsulfonates by direct anodic oxidation of electron‐rich arenes. The reaction mechanism features a multi‐component reaction consisting of electron‐rich arenes, an alcohol of choice and excess SO2 in an acetonitrile‐HFIP reaction mixture. In‐situ formed monoalkyl sulfites are considered as key intermediates with bifunctional purpose. Firstly, this species functions as nucleophile and secondly, excellent conductivity is provided. Several primary and secondary alcohols and electron‐rich arenes are implemented in this reaction to form the alkyl arylsulfonates in yields up to 73 % with exquisite selectivity. Boron‐doped…
Disordered sodium alkoxides from powder data: crystal structures of sodium ethoxide, propoxide, butoxide and pentoxide, and some of their solvates
2021
The crystal structures of NaOEt, NaOPr, NaOBu and NaOAm (Am = amyl = pentyl) were determined from powder data. These compounds crystallize in an anti-PbO structure in the space groups P 21 m and P4/nmm. Additionally, solvates with the composition NaOEt·2EtOH, NaOPr·2PrOH, NaOiPr·5iPrOH and NaOtAm·tAmOH were synthesized, and their structures were determined from single crystals. They form interesting chain structures of different compositions and topologies.
Perfil cognitivo de los alcohólicos abstinentes durante un periodo de tiempo prolongado en comparación con un grupo de hombres que no consumen alcohol
2018
Scarce studies have focused on the cognitive profile of chronic alcoholic men after long-term abstinence. Thus, we examined neuropsychological differences between long-term abstinent alcoholics for an average of 3.2 years ( n = 40, LTAA; age = 45.55 ± 8.99) and matched for socio-demographic variables with non-alcoholic controls ( n = 39; age = 42.05 ± 11.33). To this aim, we employed a neuropsychological assessment battery covered relevant cognitive domains: IQ, memory, attention, executive functions and empathy. LTAA presented deficits in abstract reasoning, speed processing, sustained attention, working and long-term memory (verbal and visuospatial), cognitive flexibility, inhibition and …
Expert appraisal of criteria for assessing gaming disorder: An international Delphi study
2021
Background and aims Following the recognition of ‘internet gaming disorder’ (IGD) as a condition requiring further study by the DSM‐5, ‘gaming disorder’ (GD) was officially included as a diagnostic entity by the World Health Organization (WHO) in the eleventh revision of the International Classification of Diseases (ICD‐11). However, the proposed diagnostic criteria for gaming disorder remain the subject of debate, and there has been no systematic attempt to integrate the views of different groups of experts. To achieve a more systematic agreement on this new disorder, this study employed the Delphi expert consensus method to obtain expert agreement on the diagnostic validity, clinical util…
Mboat7 down-regulation by hyper-insulinemia induces fat accumulation in hepatocytes.
2020
Background: Naturally occurring variation in Membrane-bound O-acyltransferase domain-containing 7 (MBOAT7), encoding for an enzyme involved in phosphatidylinositol acyl-chain remodelling, has been associated with fatty liver and hepatic disorders. Here, we examined the relationship between hepatic Mboat7 down-regulation and fat accumulation. Methods: Hepatic MBOAT7 expression was surveyed in 119 obese individuals and in experimental models. MBOAT7 was acutely silenced by antisense oligonucleotides in C57Bl/6 mice, and by CRISPR/Cas9 in HepG2 hepatocytes. Findings: In obese individuals, hepatic MBOAT7 mRNA decreased from normal liver to steatohepatitis, independently of diabetes, inflammatio…
Characterization of the alcoholic fraction of vegetable oils by derivatization with diphenic anhydride followed by high-performance liquid chromatogr…
2008
Abstract Aliphatic and triterpene alcohols present in vegetable oils have been identified and determined by HPLC using UV–vis and MS detection after previous derivatization with diphenic anhydride. The alcoholic fraction was obtained by saponification, extraction and TLC (according to the European Union official procedure). Derivatization was performed in tetrahydrofuran in the presence of suspended grinded urea, which increases the reaction rate and yield. Derivatized extracts were chromatographed on a C8 column using gradient elution with acetonitrile/water mixtures containing 0.1% acetic acid, with UV–vis followed by negative-ion mode MS detection. Using linear discriminant analysis of t…