Kinetic Solvent Effects in Organic Reactions

This article reviews prior work studying reaction kinetics in solution, with the goal of using this information to improve detailed kinetic modeling in the solvent phase. Both experimental and computational methods for calculating reaction rates in liquids are reviewed. Previous studies, which used such methods to determine solvent effects, are then analyzed based on reaction family. Many of these studies correlate kinetic solvent effect with one or more solvent parameters or properties of reacting species, but it is not always possible, and investigations are usually done on too few reactions and solvents to truly generalize. From these studies, we present suggestions on how best to use data to generalize solvent effects for many different reaction types in a high throughput manner.</jats:p

Kinetic Solvent Effects in Organic Reactions

This article reviews prior work studying reaction kinetics in solution, with the goal of using this information to improve detailed kinetic modeling in the solvent phase. Both experimental and computational methods for calculating reaction rates in liquids are reviewed. Previous studies, which used such methods to determine solvent effects, are then analyzed based on reaction family. Many of these studies correlate kinetic solvent effect with one or more solvent parameters or properties of reacting species, but it is not always possible, and investigations are usually done on too few reactions and solvents to truly generalize. From these studies, we present suggestions on how best to use data to generalize solvent effects for many different reaction types in a high throughput manner.</jats:p

Kinetic Solvent Effects in Organic Reactions

&lt;div&gt; &lt;div&gt; &lt;div&gt; &lt;p&gt;This article reviews prior work studying reaction kinetics in solution, with the goal of using this information to improve detailed kinetic modeling in the solvent phase. Both experimental and computational methods for calculating reaction rates in liquids are reviewed. Previous studies, which used such methods to determine solvent effects, are then analyzed based on reaction family. Many of these studies correlate kinetic solvent effect with one or more solvent parameters or properties of reacting species, but it is not always possible, and investigations are usually done on too few reactions and solvents to truly generalize. From these studies, we present suggestions on how best to use data to generalize solvent effects for many different reaction types in a high throughput manner. &lt;/p&gt; &lt;/div&gt; &lt;/div&gt; &lt;/div&gt;</jats:p

Extending Reaction Mechanism Generator to Silicon Hydride Chemistry

Understanding the gas-phase chemistry of silicon hydrides is the first step to building a realistic kinetic model for chemical vapor deposition (CVD). Functionality for thermodynamic and kinetic data estimation of silicon hydrides was added to the open-source software Reaction Mechanism Generator (RMG). Using the updated RMG, a detailed kinetic model was built for SiH₄ thermal decomposition. The generated model was used to perform reactor simulations at various process conditions for comparison to prior SiH₄ decomposition experiments in a flow tube. Results show that the RMG-generated model can reasonably replicate experimental results for SiH₄ concentration profiles at different temperatures and residence times. While the effect of changing initial SiH₄ concentration is not captured, a first pass sensitivity analysis reveals that reasonable errors in reaction rates could contribute to the discrepancy

Kinetic data for manuscript describing the AutoTST algorithm for automated Transition State Theory calculations of chemical reaction rates.

<p>isoButanolModel.tgz contains the kinetic model for isobutanol from http://dx.doi.org/10.1016/j.combustflame.2011.12.017  with the chemical structures of the species identified, and a script used to parse the model, categorize reactions, and attempt transition state searches.</p> <p><br></p> <p>CanThermInputOutput.tgz contains files for 781 reactions in the above mechanism belonging to the reaction families Hydrogen Abstraction, Intramolecular Hydrogen Migration, and Radical Addition to a Multiple Bond, and the 282 species they involve. For each is provided the Gaussian '09 log file (which includes the input file) for the species or transition state calculation with M062X/MG3S, and input files for CanTherm package to process these log files and calculate the reaction kinetics. Also provided, in the form of a README file, is a shell script which will install the necessary software and run all the calculations, reproducing the output files (which are also included).</p

Data from: The effect of CAG repeats length on differences in hirsutism among healthy Israeli women of different ethnicities

Purpose: Variations in the degree of hirsutism among women of different ethnic backgrounds may stem from multiple etiologies. Shorter length of the polymorphic CAG repeats of the androgen receptor (AR) gene may be associated with increased activity of the receptor leading to hirsutism. We hypothesized that there are ethnic differences in the degree of hirsutism that is unrelated to androgen levels among Israeli women, and that the CAG repeats length may contribute to these differences. Anti-androgenic therapies, such as spironolactone, could be suggested if a shorter CAG repeats length is found to affect the difference in the degree of hirsutism between the ethnic groups. Methods: Healthy Israeli Jewish women aged 18-45 years of Ashkenazi and non-Ashkenazi origin were invited to participate. Hirsutism was assessed using the simplified Ferriman-Gallwey (sFG) score, and serum total testosterone levels were measured as well. The CAG repeats length was determined by PCR. Methylation-sensitive methods were used to detect the fractional activity of each allele, and the weighted mean was calculated for the CAG repeats length. Results: One-hundred and eight women were recruited (49 Ashkenazi and 59 non-Ashkenazi). The Ashkenazi women had a significantly lower degree of hirsutism (P<0.01), lower mean BMI (P=0.003), total testosterone levels (P=0.017), and longer weighted bi-allelic CAG repeats mean (P=0.015) compared to non-Ashkenazi women. For the group as a whole, there was a significant negative correlation between the number of CAG repeats in the AR gene and the sFG score, while the number of repeats was not related to testosterone levels. Stepwise logistic regression revealed that ethnic origin and the CAG repeats length were the strongest factors affecting hirsutism (P<0.001, P=0.03, respectively). Conclusions: There is a significant difference in the degree of hirsutism between Ashkenazi and non-Ashkenazi women in Israel that is partially explained by CAG repeats length