Preparation of aromatic polyesters of hindered phenols by acid interchange polycondensation. 1. Solvent effects

1981 ◽  
Vol 20 (2) ◽  
pp. 336-338 ◽  
Author(s):  
Robert W. Stackman
Keyword(s):  
Solvent Effects ◽  
Hindered Phenols ◽  
Aromatic Polyesters

Solvent effects on the infra-red spectra of hindered phenols

1960 ◽  
Vol 254 (1276) ◽  
pp. 119-128 ◽  
Keyword(s):  
Solvent Effects ◽  
Steric Hindrance ◽  
Dynamic Equilibrium ◽  
Solvent Molecule ◽  
Thermal Agitation ◽  
Oh Groups ◽  
Infra Red ◽  
Hindered Phenols ◽  
Hindered Phenol ◽  
In Transit

The effects of variation in the shapes of the solvent and solute molecules have been studied in the hindered phenol series. When a solvent/solute complex is broken by thermal agitation it seems that reassociation of the phenolic OH with another solvent molecule occurs very rapidly. However, the introduction of bulky substituents in the immediate neighbourhood of the OH group lengthens the time between collisions suitably oriented for association. It then becomes possible to detect free OH absorptions corresponding to solute molecules in transit from one molecular association to another. These occur even in such strongly bonding solvents as ethers, and the proportions increase with the complexity of the hindering groups. Similar effects are found when a hindered phenol is examined in a series of solvents of increasing complexity, confirming that there is a dynamic equilibrium between free and associated OH groups. The OH group in the hindered phenols is largely coplanar and only in the 2,6-di- tert. -butyl derivative is there any direct steric hindrance to the approach of the solvent molecule.

Kinetic Solvent Effects in Organic Reactions

2017 ◽  
Author(s):  
Belinda Slakman ◽  
Richard West
Keyword(s):  
Solvent Effect ◽  
Reaction Kinetics ◽  
Computational Methods ◽  
High Throughput ◽  
Kinetic Modeling ◽  
Solvent Effects ◽  
Reaction Rates ◽  
Prior Work ◽  
Solvent Phase ◽  
High Throughput Manner

<div> <div> <div> <p>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. </p> </div> </div> </div>

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