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Dynamics of the Staudinger Reaction.
Wei Quan Tian1, Yan Alexander Wang1
1Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada.
Journal of Chemical Theory and Computation
|December 8, 2015
Summary
The Staudinger reaction
Area of Science:
- Computational Chemistry
- Organic Reaction Mechanisms
Background:
- The Staudinger reaction is a crucial organic transformation.
- Understanding its reaction pathway is key for synthetic applications.
Purpose of the Study:
- To elucidate the mechanism of the Staudinger reaction between phosphane and azide.
- To investigate the influence of temperature and solvent effects on the reaction pathway.
Main Methods:
- Atom-centered Density Matrix Propagation (ADMP) approach.
- Ab initio molecular dynamics (AIMD) simulations.
- Density functional theory (DFT) calculations.
- Molecular orbital analysis.
Main Results:
- The cis initial attack pathway is dominant at room temperature.
- Electrostatic interactions, charge transfer, and covalent overlap facilitate the initial attack.
- Phosphane rotation and vibrations aid in reaching the transition state.
- Increased polarizability correlates with potential energy changes, indicating solvent stabilization.
Conclusions:
- Small substituents on phosphane can accelerate the Staudinger reaction.
- Polar solvents effectively stabilize transition states and lower reaction barriers, facilitating the overall reaction.
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