Predicting Chemical Reactivity from the Charge Density through Gradient Bundle Analysis: Moving beyond Fukui
Amanda Morgenstern1, Timothy R Wilson1, M E Eberhart1
1Molecular Theory Group, Colorado School of Mines , Golden, Colorado 80401, United States.
The Journal of Physical Chemistry. A
|May 19, 2017
Summary
Predicting chemical reactivity is simplified by analyzing gradient bundle volumes. This method, based on electron density, accurately forecasts electrophilic attack sites in molecules like fluorine and carbon monoxide.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Chemical Reactivity Theory
Background:
- Predicting chemical reactivity is crucial for synthetic chemistry.
- Conceptual density functional theory (DFT) uses atom condensed Fukui functions to predict reaction sites.
- Regioselectivity is often determined by electrophilic or nucleophilic attack predictions.
Purpose of the Study:
- To introduce a novel method for predicting electrophilic attack regions within atoms.
- To demonstrate that this prediction relies solely on the charge density of neutral molecules.
- To compare stereoselectivity information using gradient bundle condensed Fukui functions.
Main Methods:
- Analysis of gradient bundle volumes derived from molecular charge density.
- Calculation of gradient bundle condensed Fukui functions.
- Application to small molecules: molecular fluorine, oxygen, nitrogen, carbon monoxide, and hydrogen cyanide.
Main Results:
- Gradient bundle volume analysis successfully predicts the most probable regions for electrophilic attack.
- The method's reliance on neutral molecule charge density simplifies reactivity predictions.
- Gradient bundle condensed Fukui functions offer a new approach for assessing stereoselectivity.
Conclusions:
- Gradient bundle volume analysis provides an effective and simplified approach to predicting chemical reactivity and regioselectivity.
- This method offers a valuable tool for computational chemists studying reaction mechanisms.
- The study highlights the potential of charge density analysis for understanding molecular interactions.
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