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Talk:Mod:Module1dc

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Cp dimers: your structures and energies are fine. However, you have mixed up the endo and exo isomers. You conclude that the endo isomer is more stable (in fact the exo isomer is lower in energy), but then state that this means that it's formed under kinetic control! More explanation needed as to the orbital interactions responsible for endo-selectivity: in fact similar HOMO/LUMO primary interactions in both cases! For the hydrogenation, you should have tried to relate your energies to specific structural features in the products.

NAD: structures for 5 look OK, although your discussion is a bit confusing. Energies for 7 seem high, but I can't see if there's anything wrong with the structures as I can't rotate them. You haven't explained the stereochemical outcome with 7. How do your structures differ in terms of which face of the molecule the C=O is on?

Taxol: again, your energies are OK I think, but I can't analyse your structures as I can't rotate them. In fact a "carbonyl down" isomer should be lowest in energy, and it's not clear to me that you established this. Nor have you explained the low reactivity of the alkene in structural terms - why is it "hyperstable"?

Carbene: Orbitals are OK, although a bit confusing as to which results are for 12 and which for the dihydro derivative. IR stretches for C=C also OK, although you haven't discussed any changes in C=C bond length.

Mini-project: Nice choice of example. The sp2-carbons all seem quite a way off to me - any ideas why? It would have been good if you'd tried to quantify how well the experimental and calculated data match in the two cases, and also how well 13C differentiates the two isomers. I agree that NOESY (a 2D NMR method!) would be the best way to tell them apart, and that 3-bond H-C J values wouldn't be much use.

Overall, you should have put more "chemical" thought and reasoning into your discussion. There are quite a few incorrect or incomplete statements. But you did manage to get most of the computation done OK!