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Talk:Mod5:mathieu.fox08

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Cp: Energies are fine for 1 and 2 (too many dec. places though!) You are right that the endo-isomer is kinetically preferred, but wrong about the reason. The endo-isomer suffers more from sterics than the exo one (as in the products) - so we need another explanation as to why it is preferred (usually, stabilising "secondary orbital interactions" present in the endo-TS but not the exo-TS are invoked). 3 and 4 energies good.

NAD: Like the idea of systematically testing different starting points. Are the angles quoted for the minimised structures, or for the starting structures? What forcefield was used? It's a pity you haven't given your structures for me to look at.

Taxol: Your structure 10 is actually the "up" isomer. Your 9 has the wrong alkene geometry unfortunately; also the 6-ring is in a boat conformation.

CCl2: Orbitals and stretches look OK. Did you look at the bond lengths? Note that the OH-substitued alkene is definitely electron rich (remember, it's an enol!)

Mini-project: Nice example! Note that your calculation to convert a ratio of 7:1 into an energy value gives you the DIFFERENCE in energy between the two TSs, not the "total change in Gibbs free energy" (also you are out by a factor of 1000 - it should be 4.8kJ/mol). Nice TS analysis! :) Your calcs look good - did you think about which particular carbons show a big discrepancy, and why?