Schlenk equilibrium
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The Schlenk equilibrium is a chemical equilibrium named after its discoverer Wilhelm Schlenk taking place in solutions of Grignard reagents.
The process described is an equilibrium between two equivalents of an alkyl or aryl magnesium halide on the left of the equation and on the right side one equivalent of the dialkyl or diaryl magnesium compound and magnesium halide salt.
The position of the equilibrium is influenced by solvent and temperature, the nature of the various substituents and the presence of impurities. In solvents containing an ether linkage such as diethyl ether or tetrahydrofuran the equilibrium is in favor of the alkyl or aryl magnesium halide because magnesium coordinates to the oxygen atom of the ether forming a lewis acid to base complex. With dioxane on the other hand this coordination is favorable for the magnesium halide salt and the equilibrium is shifted to the right.
Complexity is added to this equilibrium because the organomagnesium halide species in solution are capable of forming dimers and trimers etc.
[edit] See also
[edit] References
- ↑ W. Schlenk, W. Schlenk, Chem. Ber. 62, 920 1929 Note: the authors are father and son
- ↑ Grignard Reagents: New Developments H. G. Richey (Editor) ISBN 0-471-99908-3
