scholarly journals Prediction of NHC-catalyzed chemoselective functionalizations of carbonyl compounds: a general mechanistic map

2020 ◽  
Vol 11 (27) ◽  
pp. 7214-7225 ◽  
Author(s):  
Xue Li ◽  
Jun Xu ◽  
Shi-Jun Li ◽  
Ling-Bo Qu ◽  
Zhongjun Li ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Carbonyl Compounds

A novel index ω + N can be used to predict the chemoselectivity according to the general NHC-catalyzed reaction mechanism.

scholarly journals A reaction mechanism-based prediction of mutagenicity: α-halo carbonyl compounds adduct with DNA by SN2 reaction

2018 ◽  
Vol 43 (3) ◽  
pp. 203-211
Author(s):  
Yu Haranosono ◽  
Hiroki Ueoka ◽  
Gakushi Kito ◽  
Shingo Nemoto ◽  
Masaaki Kurata ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Carbonyl Compounds

Cu(I)-Bis(phosphine) Dioxides as catalysts for the Enantioselective α-Arylation of Carbonyl Compounds

Synlett ◽  
2021 ◽  
Author(s):  
Margarita Escudero-Casao ◽  
Giulia Licini ◽  
Manuel Orlandi
Keyword(s):  
Reaction Mechanism ◽  
Transition Metal ◽  
Catalytic System ◽  
Carbonyl Compounds ◽  
Research Area ◽  
Metal Catalysts ◽  
Transition Metal Catalysts ◽  
Transition Metal Catalyzed ◽  
Metal Catalyzed

The transition metal catalyzed α-arylation of carbonyl compounds was first reported by Buchwald and Hartwig in 1997. This transformation has been used and studied extensively over the last two decades. Enantioselective variants were also developed that allow for controlling the product stereochemistry. However, these suffer several limitations in the context of formation of tertiary stereocenters. Presented here is our group’s contribution to this research area. The chiral Cu-bis(phosphine) dioxides catalytic system that we reported allowed accessing the enantioselective α-arylation of ketones that were not suitable for this transformation before in good yields and er up to 97.5:2.5. Preliminary insight and speculation concerning the reaction mechanism involving the unusual pairing of bis(phosphine) dioxides with transition metal catalysts is also given.

scholarly journals Combustion behaviors of hydrogenated and unhydrogenated colophony esters/petroleum resins using TG-FTIR and DFT analysis

2021 ◽  
Author(s):  
Dan Zhou ◽  
Xiaopeng Chen ◽  
Jiezhen Liang ◽  
Xiaojie Wei ◽  
Chenghong Wu ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Reaction Mechanism ◽  
Dft Calculations ◽  
Carbonyl Compounds ◽  
Density Functional ◽  
Functional Theory ◽  
Master Plots ◽  
Glycerol Ester ◽  
Friedman Method ◽  
Combustion Behaviors

The combustion behavior of tackifying resins (such as glycerol ester of colophony/hydrogenated colophony and C9/hydrogenated C9 petroleum resin, namely GEC, GEHC, C9PR and HC9PR, respectively) were investigated using TG-FTIR and density functional theory (DFT) analyses. Results from combustion characteristics indicate tackifying resins and their wastes are a promising fuel for generating energy. The average activation energies obtained by Friedman method for GEC, GEHC, C9PR and HC9PR were 223.51, 162.16, 166.52 and 116.20 kJ/mol, respectively, revealing that (H)C9PR were more readily combustible than GE(H)C, and their hydrogenated products burned more easily than their unhydrogenated ones, which were strongly supported by the TG-FTIR results. DFT calculations also show that the bond dissociation energy of C-C bond of GEC is higher than those of C9PR and GEHC. The best appropriate reaction mechanism evaluated by integral master plots is f(α)=3(1-α)2/3. Volatiles are mainly composed of H2O, CH4, CO2, CO, alcohol, aromatic and carbonyl compounds.

PREPARATION OF 1,1-DIARYLETHENES BY MCMURRY REACTION: MECHANISM AND GEOMETRY SELECTION

2006 ◽  
Vol 20 (25n27) ◽  
pp. 4595-4600 ◽  
Author(s):  
TAKAAKI ISHIDUKA ◽  
MASAO TSUKAYAMA ◽  
YASUHIKO KAWAMURA
Keyword(s):  
Reaction Mechanism ◽  
Conformational Analysis ◽  
Spin Density ◽  
Molecular Orbital ◽  
Carbonyl Compounds ◽  
Anion Radical ◽  
Molecular Orbital Calculations ◽  
Coupling Reactions ◽  
Reaction Conditions ◽  
Mcmurry Reaction

The McMurry crossed coupling reactions of p,p′-disubstituted benzophenones (1) with pivalaldehyde (Pv) gave the corresponding ethenes (2) in fair to excellent yield. The observed geometrical selectivity is varied depending on a kind of p-substituent of the aromatic moiety of 1, when p′-substituent is limited to methyl. According to the known reaction mechanism, the reason why the geometry selection occurred is discussed by a conformational analysis of a possible intermediate, titanium bound pinacolate, and molecular orbital calculations of the starting carbonyl compounds. As a result, the selection is caused by electronic and stereochemical structures of anion radical of 1 and approaching mode of Pv anion radical to them. Distribution of a spin density and unsymmetrical nature of two aromatic moieties of anion radical of 1 provide predetermined pathway to bring about the pinacolate without any rotational conversion under the reaction conditions. Subsequent workup affords 2 with the observed geometry.

scholarly journals Thiocyanation of α-amino carbonyl compounds for the synthesis of aromatic thiocyanates

2020 ◽  
pp. 174751982092355
Author(s):  
Niannian Yi ◽  
Mingjing Ouyang ◽  
Huimin Liu ◽  
Miao Yan ◽  
Xiaoyong Wen ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Transition Metal ◽  
Dimethyl Sulfoxide ◽  
Carbonyl Compounds ◽  
High Efficiency ◽  
Potassium Thiocyanate ◽  
Metal Catalyst ◽  
Reaction Conditions ◽  
Transition Metal Catalyst ◽  
Related Literature

A procedure for K2S2O8-mediated thiocyanation of α-amino carbonyl compounds has been developed for the synthesis of aromatic thiocyanates. A series of α-amino carbonyl compounds have been investigated, and the desired products are obtained in 74%–93% yields. This strategy has the advantages of simple reaction conditions without use of a transition-metal catalyst, high regioselectivity, and high efficiency. Moreover, we found that arylamine thiocyanates can also be obtained from α-amino carbonyl compounds and potassium thiocyanate in the presence of CoCl2·6H2O, I2, and dimethyl sulfoxide through the cleavage of the C–N bond. To explore the reaction mechanism, we designed several control experiments and proposed a possible mechanism using the experimental results and related literature reports.

scholarly journals Fe(OTf) 3 -catalysed Friedel–Crafts reaction of benzenoid arenes with α,β-unsaturated carbonyl compounds: easy access to 1,1-diarylalkanes

2017 ◽  
Vol 4 (10) ◽  
pp. 170748 ◽  
Author(s):  
Aditya Bhattacharya ◽  
Pushpendra Mani Shukla ◽  
Biswajit Maji
Keyword(s):  
Reaction Mechanism ◽  
Cinnamic Acid ◽  
Efficient Method ◽  
Carbonyl Compounds ◽  
Acid Ester ◽  
Easy Access ◽  
Alkylation Reaction ◽  
Isotopic Labelling ◽  
Isotopic Labelling Experiments

A simple and efficient method for the synthesis of 1,1-diarylalkanes via the Friedel–Crafts-type alkylation reaction of electron-rich arenes with cinnamic acid ester derivatives or chalcones is reported. Iron triflate has been found to be the best catalyst for the Friedel–Crafts-type alkylation reaction with α,β-unsaturated carbonyl compounds. This reaction afforded β,β-diaryl carbonyl compounds in good yields (65–93%) and with excellent regioselectivities. Remarkably, this method is also compatible with a variety of indoles to provide 3-indolyl-aryl carbonyl compounds in excellent yields. Great efforts have been made to deduce a plausible reaction mechanism based on isotopic labelling experiments.

Theoretical Study on the Hydroboration of α,β-Unsaturated Carbonyl Compounds Catalyzed by Metal-Free Complex and Subsequent C−C Coupling with Acetonitrile

2021 ◽  
Author(s):  
Ling Zhu ◽  
Lin Zhang ◽  
Zuoyin Yang ◽  
Min Pu ◽  
Ming Lei
Keyword(s):  
Density Functional Theory ◽  
Reaction Mechanism ◽  
Carbonyl Compounds ◽  
Density Functional ◽  
Theoretical Study ◽  
Dft Method ◽  
Functional Theory ◽  
Metal Free

Herein density functional theory (DFT) method was employed to explore the reaction mechanism of selective hydroboration of α,β-unsaturated carbonyl compounds catalyzed by the metal-free complex, 1,3,2-diazaphospholene (DAP). The whole reaction...

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