Conductance Study of Benzyl Bromide Reaction with Cyclicamines in Aqueous-Ethanol Medium

2018 ◽  
Vol 7 (3.3) ◽  
pp. 143
Author(s):  
Veerati Radhika ◽  
. .
Keyword(s):  
Electrostatic Interactions ◽  
Mixed Solvent ◽  
Aqueous Ethanol ◽  
Benzyl Bromide ◽  
Frontier Molecular Orbital ◽  
Orbital Interactions ◽  
R Factor ◽  
Ethanol Medium ◽  
Solvation Of Ions ◽  
Homo Lumo

Nucleophilic substitution reaction of benzyl bromide and cyclicamines in ethanol aqueous intermediate reactivity can suggest that the nucleophile increases through their pKa values. A linear correlation exists between computed values of the dipole moment, rate and electronegativity of the nucelophiles. The two reactants suggest that frontier molecular orbital interactions ion-solvation and correlation of time with the HOMO-LUMO breach of that the reaction.  But it is not orbital controlled as well as forbidden by the electrostatic interactions along with mixed solvent composition between the reactants. The influence on the solvation of ions before reaction has been discuss with facilitate by R-factor. Thermodynamic properties are evaluate and report. The consequences of the learning to be interpreted in terms of ion-solvent exchanges and solvent properties comparing with electrostatic interaction between the reactants.   

Study on the Synthesis of Carboxymethylpachyman in the Aqueous-Ethanol Medium with the Assistance of Ultrasonics

2011 ◽  
Vol 236-238 ◽  
pp. 2810-2814
Author(s):  
Yong Jiang Wang ◽  
Xue Qian Wu ◽  
Shi Wang Liu ◽  
Yuan Feng Wu ◽  
Yan Ping Zhang
Keyword(s):  
Biological Activity ◽  
Aqueous Ethanol ◽  
Reaction Medium ◽  
Volume Ratio ◽  
Value Added ◽  
Poria Cocos ◽  
A Value ◽  
Ethanol Medium ◽  
Favorable Conditions ◽  
Carboxymethyl Pachyman

Water-insoluble β - ( 1 - 3 ) – D - glucan isolated from the sclerotium of Poria cocos hardly exhibits biological activity. Therefore, it is advantageous to produce a value-added product from Poria cocos. We extracted the β - ( 1 - 3 ) – D - glucan from the sclerotium of Poria cocos and synthesized a carboxymethylated derivative, carboxymethyl-pachyman (CMP). The influences on the degrees of substitution ( DS ) of CMP, for example, volume ratio of ethanol to water, [NaOH]/[MCA] ratio, reaction temperature and reaction time have been examined, respectively. The most favorable conditions for pachyman carboxymethylation are obtained with a [NaOH]/[MCA] ratio of 1.5, at 45°C for 60 minutes with a reaction medium consisting of a ethanol/water 80:20 (v/v) mixture.

Adsorption properties of manganese oxides prepared in aqueous-ethanol medium toward Sr(II) ions

2019 ◽  
Vol 321 (1) ◽  
pp. 243-253 ◽  
Author(s):  
A. I. Ivanets ◽  
V. V. Milutin ◽  
V. G. Prozorovich ◽  
T. F. Kouznetsova ◽  
N. A. Nekrasova
Keyword(s):  
Manganese Oxides ◽  
Aqueous Ethanol ◽  
Adsorption Properties ◽  
Ethanol Medium

Substituent effects in naphthalene. II. The strengths of the 4, 5, 6, 7, and 8-substituted 2-naphthoic acids

1965 ◽  
Vol 18 (9) ◽  
pp. 1365 ◽  
Author(s):  
PR Wells ◽  
W Adcock
Keyword(s):  
Electrostatic Interactions ◽  
Aqueous Ethanol ◽  
Substituent Effects ◽  
Simple Expression ◽  
Dipole Orientation ◽  
Aromatic Substituent ◽  
Resonance Effects ◽  
Naphthoic Acid ◽  
Inductive Effects ◽  
Substituted 1

The apparent pKa values of 44 substituted 2-naphthoic acids, six substituted 1-naphthoic acids, and the unsubstituted naphthoic acids have been determined for 50% v/v aqueous ethanol at 25�. The ΔpK values are examined in terms of Dewar and Grisdale's simple expression for aromatic substituent effects. This expression proves to be fairly satisfactory, but takes no account of substituent dipole orientation, secondary resonance effects, nor π-inductive effects. A survey of the naphthoic acid strengths demonstrates the importance of these factors. In particular, unambiguous evidence for the important role played by direct electrostatic interactions is obtained.

Proline-Catalyzed Simple and Efficient Synthesis of 1,8-Dioxo-decahydroacridines in Aqueous Ethanol Medium

2008 ◽  
Vol 39 (2) ◽  
pp. 228-241 ◽  
Author(s):  
K. Venkatesan ◽  
Suresh S. Pujari ◽  
Kumar V. Srinivasan
Keyword(s):  
Aqueous Ethanol ◽  
Efficient Synthesis ◽  
Ethanol Medium

scholarly journals Strategies and Software for Machine Learning Accelerated Discovery in Transition Metal Chemistry

2018 ◽  
Author(s):  
Aditya Nandy ◽  
Chenru Duan ◽  
Jon Paul Janet ◽  
Stefan Gugler ◽  
Heather Kulik
Keyword(s):  
Machine Learning ◽  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Density Functional ◽  
Open Shell ◽  
Frontier Molecular Orbital ◽  
Data Set ◽  
Homo Level ◽  
Homo Lumo

<p>Machine learning the electronic structure of open shell transition metal complexes presents unique challenges, including robust and automated data set generation. Here, we introduce tools that simplify data acquisition from density functional theory (DFT) and validation of trained machine learning models using the molSimplify automatic design (mAD) workflow. We demonstrate this workflow by training and comparing the performance of LASSO, kernel ridge regression (KRR), and artificial neural network (ANN) models using heuristic, topological revised autocorrelation (RAC) descriptors we have recently introduced for machine learning inorganic chemistry. On a series of open shell transition metal complexes, we evaluate set aside test errors of these models for predicting the HOMO level and HOMO-LUMO gap. The best performing models are ANNs, which show 0.15 and 0.25 eV test set mean absolute errors on the HOMO level and HOMO-LUMO gap, respectively. Poor performing KRR models using the full 153-feature RAC set are improved to nearly the same performance as the ANNs when trained on down-selected subsets of 20-30 features. Analysis of the essential descriptors for HOMO and HOMO-LUMO gap prediction as well as comparison to subsets previously obtained for other properties reveals the paramount importance of non-local, steric properties in determining frontier molecular orbital energetics. We demonstrate our model performance on diverse complexes and in the discovery of molecules with target HOMO-LUMO gaps from a large 15,000 molecule design space in minutes rather than days that full DFT evaluation would require. </p>

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