As we have been involved in docking, SAR, QSAR and DFT calculation using Schrödinger software, I started thinking about possibility of using any software for theoretical calculation of stereoselectivity in organic molecules. It can be helpful to organic chemists to check the probabilities/optimization of conditions for the formation "ee" and "de" in product before doing experiments. If you have any idea, please comment on this.
To my opinion you can calculate the thermodynamic composition of diastereomers with DFT. (The pure thermodynamic composition is obtained when there is an equilibrium between the diastereomers in the reaction). However, many times you have kinetic control in asymmetric synthesis, especially in asymmetric catalysis. This is intrinsically the case with enantiomers as these have equal energies. In this cases you need to know the energy differences between the transition states (delta-delta G) of the reaction and thus also the actual structures of the transition states. You can probably model this in some asymmetric syntheses, but that is then another computational job. Furthermore in some asymmetric catalytic reaction the exact mechanism is still uncertain. Thus you don't know what to model. In summary, I think you can calculate d.e. in some cases, while calculation of e.e. is probably much more difficult if not impossible yet for many systems.
Imre - exactly! Reaction kinetics is everything in majority of asymmetric syntheses. It is a function not only of the reactant structures, but multiple other factors come into play, like the effects of concentration, pH, temperature, pressure, complex catalytic interactions with trace components, etc. A practicing chemist might just not feel that such calculations have practical value... until proven convincingly, of course :)
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