Reactions of chemically activated C9H9 species II: The reaction of phenyl radicals with allene and cyclopropene, and of benzyl radicals with acetyleneElectronic supplementary information (ESI) available: Full [C9H9] reaction scheme. Additional quantum chemical calculations not reported yet in earlier publications. Full product distribution and over-all rate coefficient listings, both uncorrected and effective data, for all reaction conditions examined. For the most important products, tables are included listing the yield as function of temperature and pressure. Modified Arrhenius fits for the over-all TST rate coefficient and the TST rate coefficient of the different entrance channels are listed for different temperature intervals. See http://www.rsc.org/suppdata/cp/b3/b303908k/ or contact the authors directly, or download from the website http://arrhenius.chem.kuleuven.ac.be.

2003 ◽  
Vol 5 (13) ◽  
pp. 2807 ◽  
Author(s):  
Luc Vereecken ◽  
Jozef Peeters
Keyword(s):  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Rate Coefficient ◽  
Product Distribution ◽  
Reaction Scheme ◽  
Supplementary Information ◽  
Reaction Conditions ◽  
Phenyl Radicals ◽  
Benzyl Radicals ◽  
Temperature And Pressure

scholarly journals Stereoselective Synthesis of Multisubstituted Cyclohexanes by Reaction of Conjugated Enynones with Malononitrile in the Presence of LDA

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5920
Author(s):  
Anastasiya V. Igushkina ◽  
Alexander A. Golovanov ◽  
Irina A. Boyarskaya ◽  
Ilya E. Kolesnikov ◽  
Aleksander V. Vasilyev
Keyword(s):  
Reaction Mechanism ◽  
Quantum Chemical Calculations ◽  
Relative Stability ◽  
Quantum Chemical ◽  
Room Temperature ◽  
Stereoselective Synthesis ◽  
Dft Method ◽  
Lithium Diisopropylamide ◽  
Reaction Conditions

Reaction of linear conjugated enynones, 1,5-diarylpent-2-en-4-yn-1-ones, with malononitrile in the presence of lithium diisopropylamide LDA, as a base, in THF at room temperature for 3–7 h resulted in the formation of the product of dimerization, multisubstituted polyfunctional cyclohexanes, 4-aryl-2,6-bis(arylethynyl)-3-(aryloxomethyl)-4-hydroxycyclohexane-1,1-dicarbonitriles, in yields up to 60%. Varying the reaction conditions by decreasing time and temperature and changing the ratio of starting compounds (enynone and malononitrile) allowed isolating some intermediate compounds, which confirmed a plausible reaction mechanism. The relative stability of possible stereoisomers of such cyclohexanes was estimated by quantum chemical calculations (DFT method). The obtained cyclohexanes were found to possess photoluminescent properties.

scholarly journals Thermodynamic Analysis of the Nitrogen-Containing Compounds Conversion in the Process of Diesel Fractions Hydrotreatment Based on Quantum Chemical Calculations

2020 ◽  
Vol 126 (1) ◽  
pp. 3-7
Author(s):  
E. V. Frantsina ◽  
◽  
N. I. Krivtcova ◽  
T. I. Babyi ◽  
◽  
...  
Keyword(s):  
Nitrogen Atom ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Density Functional ◽  
Density Functional Theory Method ◽  
Reaction Scheme ◽  
Functional Theory ◽  
Monoaromatic Hydrocarbons ◽  
Nitrogen Containing Compounds ◽  
Diesel Fractions

Based on quantum chemical calculations using the DFT density functional theory method (B3LYP theoretical approximation model, basis 3-21G), thermodynamic parameters of the nitrogen-containing compounds reactions in the diesel fractions hydrotreating process at a temperature of 400°C and a pressure of 2MPa were evaluated. The following groups of nitrogen-containing compounds: monoaromatic hydrocarbons position nitrogen atom in the ring, diaromatic hydrocarbons position nitrogen atom in the ring, monosubstituted diaromatic hydrocarbons with the position of the nitrogen atom in the ring, triaromatic hydrocarbons with the position of the nitrogen atom in the ring (acridine, carbazole), alkyl-substituted nitriles, aromatic nitriles, aromatic amines were identified. The probability of reactions was determined, a reaction scheme for the conversion of hydrocarbons was proposed, which can be used to develop a mathematical model of the diesel fractions hydrotreatment process taking into account the conversion of nitrogen-containing compounds.

scholarly journals Direct alkenylation of indolin-2-ones by 6-aryl-4-methylthio-2H-pyran-2-one-3-carbonitriles: a novel approach

2013 ◽  
Vol 9 ◽  
pp. 809-817 ◽  
Author(s):  
Sandeep Kumar ◽  
Ramendra Pratap ◽  
Abhinav Kumar ◽  
Brijesh Kumar ◽  
Vishnu K Tandon ◽  
...  
Keyword(s):  
Quantum Chemical Calculations ◽  
Relative Stability ◽  
Quantum Chemical ◽  
Noncovalent Interactions ◽  
Reaction Conditions ◽  
One Pot ◽  
Supramolecular Architectures ◽  
Novel Approach

A direct one-pot base-induced alkenylation of indolin-2-ones has been developed by using 6-aryl-4-methylthio-2H-pyran-2-one-3-carbonitriles. Different bases such as MeONa, NaH and t-BuONa have been used to optimize the reaction conditions to obtain the desired product. NaH in THF was found to be the most suitable for the alkenylation of indolin-2-ones. Reaction in the presence of other bases led to the formation of 1-aryl-3-methoxy/methylthio-5H-dibenzo[d,f][1,3]diazepin-6(7H)-ones. Quantum chemical calculations have been performed to explain the nature of the weak noncovalent interactions operating in the supramolecular architectures of alkenylated indoline-2-ones and to explain the relative stability of one of the tautomers with respect to the others.

Discovery of a Difluoroglycine Synthesis Method through Quantum Chemical Calculations

2020 ◽  
Author(s):  
Tsuyoshi Mita ◽  
Yu Harabuchi ◽  
Satoshi Maeda
Keyword(s):  
Quantum Chemical Calculations ◽  
Experimental Verification ◽  
Quantum Chemical ◽  
Synthesis Method ◽  
Target Product ◽  
Systematic Exploration ◽  
Hands On ◽  
Retrosynthetic Analysis ◽  
Synthetic Routes ◽  
Verification Process

The systematic exploration of synthetic pathways to afford a desired product through quantum chemical calculations remains a considerable challenge. In 2013, Maeda et al. introduced ‘quantum chemistry aided retrosynthetic analysis’ (QCaRA), which uses quantum chemical calculations to search systematically for decomposition paths of the target product and propose a synthesis method. However, until now, no new reactions suggested by QCaRA have been reported to lead to experimental discoveries. Using a difluoroglycine derivative as a target, this study investigated the ability of QCaRA to suggest various synthetic paths to the target without relying on previous data or the knowledge and experience of chemists. Furthermore, experimental verification of the seemingly most promising path led to the discovery of a synthesis method for the difluoroglycine derivative. The extent of the hands-on expertise of chemists required during the verification process was also evaluated. These insights are expected to advance the applicability of QCaRA to the discovery of viable experimental synthetic routes.

Discovery of a Difluoroglycine Synthesis Method through Quantum Chemical Calculations

2020 ◽  
Author(s):  
Tsuyoshi Mita ◽  
Yu Harabuchi ◽  
Satoshi Maeda
Keyword(s):  
Quantum Chemical Calculations ◽  
Experimental Verification ◽  
Quantum Chemical ◽  
Synthesis Method ◽  
Target Product ◽  
Systematic Exploration ◽  
Hands On ◽  
Retrosynthetic Analysis ◽  
Synthetic Routes ◽  
Verification Process

The systematic exploration of synthetic pathways to afford a desired product through quantum chemical calculations remains a considerable challenge. In 2013, Maeda et al. introduced ‘quantum chemistry aided retrosynthetic analysis’ (QCaRA), which uses quantum chemical calculations to search systematically for decomposition paths of the target product and propose a synthesis method. However, until now, no new reactions suggested by QCaRA have been reported to lead to experimental discoveries. Using a difluoroglycine derivative as a target, this study investigated the ability of QCaRA to suggest various synthetic paths to the target without relying on previous data or the knowledge and experience of chemists. Furthermore, experimental verification of the seemingly most promising path led to the discovery of a synthesis method for the difluoroglycine derivative. The extent of the hands-on expertise of chemists required during the verification process was also evaluated. These insights are expected to advance the applicability of QCaRA to the discovery of viable experimental synthetic routes.

The Nature of Chemisorbed CO2 in Zeolite A

2019 ◽  
Author(s):  
Przemyslaw Rzepka ◽  
Zoltán Bacsik ◽  
Andrew J. Pell ◽  
Niklas Hedin ◽  
Aleksander Jaworski
Keyword(s):  
Solid State ◽  
Ir Spectroscopy ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Surface Coverage ◽  
Gas Mixtures ◽  
Mas Nmr ◽  
Significant Fraction ◽  
Zeolite A

Formation of CO<sub>3</sub><sup>2-</sup> and HCO<sub>3</sub><sup>-</sup> species without participation of the framework oxygen atoms upon chemisorption of CO<sub>2</sub> in zeolite |Na<sub>12</sub>|-A is revealed. The transfer of O and H atoms is very likely to have proceeded via the involvement of residual H<sub>2</sub>O or acid groups. A combined study by solid-state <sup>13</sup>C MAS NMR, quantum chemical calculations, and <i>in situ</i> IR spectroscopy showed that the chemisorption mainly occurred by the formation of HCO<sub>3</sub><sup>-</sup>. However, at a low surface coverage of physisorbed and acidic CO<sub>2</sub>, a significant fraction of the HCO<sub>3</sub><sup>-</sup> was deprotonated and transformed into CO<sub>3</sub><sup>2-</sup>. We expect that similar chemisorption of CO<sub>2</sub> would occur for low-silica zeolites and other basic silicates of interest for the capture of CO<sub>2</sub> from gas mixtures.

Mechanistic Investigation of Rh(I)-Catalyzed Asymmetric Suzuki-Miyaura Coupling with Racemic Allyl Halides

2019 ◽  
Author(s):  
Lucy van Dijk ◽  
Ruchuta Ardkhean ◽  
Mireia Sidera ◽  
Sedef Karabiyikoglu ◽  
Özlem Sari ◽  
...  
Keyword(s):  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Experimental Studies ◽  
Mechanistic Investigation ◽  
Allyl Halides

A mechanism for Rh(I)-catalyzed asymmetric Suzuki-Miyaura coupling with racemic allyl halides is proposed based on a combination of experimental studies and quantum chemical calculations. <br>

Sign in / Sign up

Export Citation Format

Share Document