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Published on: January 30, 2019
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A quantitative approach to polar organic reactivity
1a Department Chemie der Ludwig-Maximilians-Universität München , München , Germany.
SAR and QSAR in Environmental Research
|August 29, 2015
Summary
Predicting toxic effects from covalent bonds is now possible using nucleophilicity and electrophilicity scales. These scales aid in planning organic syntheses and understanding chemical reactivity.
Area of Science:
- Chemical Biology
- Organic Chemistry
- Toxicology
Background:
- Covalent bond formation between electrophilic compounds and nucleophilic biological targets (proteins, nucleic acids) can trigger toxic effects.
- Predicting such toxicities is crucial for drug development and risk assessment.
- Existing methods for predicting reactivity are limited in scope and applicability.
Purpose of the Study:
- To present a novel method for predicting toxic effects.
- To introduce comprehensive nucleophilicity and electrophilicity scales for planning organic syntheses.
- To provide a tool for understanding and predicting chemical reactivity in biological systems.
Main Methods:
- Measurement of rate constants for reactions of benzhydrylium ions and quinone methides with nucleophiles.
- Correlation of rate constants using the equation lg k(20 °C) = sN(E + N).
- Development of kinetic and thermodynamic scales (electrophilicity E, nucleophilicity N, susceptibility sN, Lewis acidity LA, Lewis basicity LB).
Main Results:
- Construction of comprehensive nucleophilicity and electrophilicity scales.
- Development of a freely accessible database with data for 1000 nucleophiles and 260 electrophiles.
- Validation of the kinetic equation for predicting absolute rate constants.
- Development of a thermodynamic counterpart for calculating association constants.
Conclusions:
- The presented method allows prediction of toxic effects arising from covalent interactions.
- The nucleophilicity and electrophilicity scales are valuable tools for organic synthesis planning.
- The developed database and scales provide a robust framework for assessing chemical reactivity and potential toxicity.
Keywords:
Lewis acidityLewis basicityelectrophilicitykineticslinear free energy relationshipsthermodynamicsMore Related Videos
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