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Talk:Mod:kmt07231

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Cp: Structures all fine. Why exactly is the TS leading to 2 of lower energy than that leading to 1?

NAD: The two structures you've drawn are enantiomers, and so will have the same energy! Your 5a and 5b are actually the same. For 7 - the bond angles at your pyridinium N look a little odd, and the energy difference between 7a and 7b is surprisingly high.

Taxol: Structure 10 looks good. The energy for 9 is high - looks like the 6-ring is in a boat-like conformation. You haven't really identified why the alkene is unreactive in terms of structural features.

Carbene: Good structures and discussion

Mini-Project: The "reactant" JMol is strange - wrong structure?? Have a think about the relationship between your two E-isomers of the product, and why their energies are so similar! The discussion of the effect of temperature on the product ratio is a little strange. If the reaction is thermodynamically controlled (and it may not be - the Z-isomer might be preferred both kinetically AND thermodynamically) - one would expect higher temperatures to make equilibration more likely, and hence favour the thermodynamic product even more. It's always worth looking at the product yields in situations like this - is it possible that one of the two isomers is selectively consumed in another reaction?

The IR discussion is a bit long given that it was not likely to tell you much!

In the 13C: note that 13C spectra are usually run with proton decoupling, so all peaks are usually singlets. However, some of the peaks here are doublets because of coupling to F - not to conformational isomerism! Maybe I'm not clear what you mean by "degeneracy"...

Would have been good to have a quantitative comparison between calculated and experimental data.

Overall - generally good (if long-winded) discussion. I agree that NOE would be the best way to tell the isomers apart!