On the displacement reactions of organic substances in water

2005 ◽  
Vol 83 (9) ◽  
pp. 1667-1719 ◽  
Author(s):  
J MW Scott
Keyword(s):  
Free Energy ◽  
Temperature Dependence ◽  
Isotope Effects ◽  
Linear Free Energy Relationship ◽  
Linear Free Energy Relationships ◽  
Organic Substances ◽  
Linear Free Energy ◽  
Organic Halides ◽  
Displacement Reactions ◽  
Energy Relationships

The hydrolyses of a series of organic halides, nitrates, sulphonates, and perchlorates are examined from the standpoint of thermodynamics, kinetics, temperature dependence, isotope effects, the Kurz equation, and the Guthrie linear free energy relationship. The thermodynamics of several definite bimolecular displacements are also examined. Some mechanistic revisions are suggested to reach an improved accommodation with the experimental observations.Key words: kinetics, thermodynamics, hydrolytic displacements, mechanism, ionic displacements, nucleofugality, linear free energy relationships.

Establishing linear-free-energy relationships for the quadricyclane-to-norbornadiene reaction

2020 ◽  
Vol 18 (11) ◽  
pp. 2113-2119 ◽  
Author(s):  
Mads Mansø ◽  
Anne Ugleholdt Petersen ◽  
Kasper Moth-Poulsen ◽  
Mogens Brøndsted Nielsen
Keyword(s):  
Free Energy ◽  
Linear Free Energy Relationship ◽  
Linear Free Energy Relationships ◽  
Linear Free Energy ◽  
Energy Relationships ◽  
Kinetics Of ◽  
Selection Of

The kinetics of the thermal quadricyclane-to-norbornadiene (QC-to-NBD) isomerization follows a linear-free-energy relationship when using Creary radical values for a selection of aryl/cyano disubstituted derivatives.

Linear Free Energy Relationships for Transition Metal Complex Chemistry: Opportunity or Pipe Dream?

2019 ◽  
Author(s):  
Zhenzhuo Lan ◽  
Shaama Mallikarjun Sharada
Keyword(s):  
Free Energy ◽  
Transition Metal ◽  
Catalyst Design ◽  
Energy Decomposition Analysis ◽  
Linear Free Energy Relationship ◽  
Linear Free Energy Relationships ◽  
Structural Descriptors ◽  
Linear Free Energy ◽  
Energy Relationships ◽  
Geometric Effects

We propose a computational framework for developing Taft-like linear free energy relationships to characterize steric effects on the catalytic activity of transition metal complexes. The framework uses the activation strain model and energy decomposition analysis to isolate electronic and geometric effects, and identifies structural descriptors to construct the linear relationship. We demonstrate proof-of-principle for CH activation with enzyme-inspired [Cu2O2]2+ complexes, each coordinated to two identical bidentate diamine N-donors. Electronic effects are largely similar across the chosen systems and geometric effects – quantified by strain energies – are accurately captured by a linear combination of two structural descriptors. A powerful linear free energy relationship emerges that is both transferable to asymmetrically substituted complexes and independent of choice of theory. We outline steps for expanding this approach to create a generalizable Taft framework for inorganic catalyst design.

Linear Free Energy Relationships for Transition Metal Complex Chemistry: Opportunity or Pipe Dream?

2019 ◽  
Author(s):  
Zhenzhuo Lan ◽  
Shaama Mallikarjun Sharada
Keyword(s):  
Free Energy ◽  
Transition Metal ◽  
Catalyst Design ◽  
Energy Decomposition Analysis ◽  
Linear Free Energy Relationship ◽  
Linear Free Energy Relationships ◽  
Structural Descriptors ◽  
Linear Free Energy ◽  
Energy Relationships ◽  
Geometric Effects

We propose a computational framework for developing Taft-like linear free energy relationships to characterize steric effects on the catalytic activity of transition metal complexes. The framework uses the activation strain model and energy decomposition analysis to isolate electronic and geometric effects, and identifies structural descriptors to construct the linear relationship. We demonstrate proof-of-principle for CH activation with enzyme-inspired [Cu2O2]2+ complexes, each coordinated to two identical bidentate diamine N-donors. Electronic effects are largely similar across the chosen systems and geometric effects – quantified by strain energies – are accurately captured by a linear combination of two structural descriptors. A powerful linear free energy relationship emerges that is both transferable to asymmetrically substituted complexes and independent of choice of theory. We outline steps for expanding this approach to create a generalizable Taft framework for inorganic catalyst design.

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