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Talk:Mod:pz1122

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Cyclopentadiene dimer

Good results and nice analysis. I was a bit baffled by your choice of angle as shown in the four Jmols (you should put these into a numbered table so that others can easily refer to the table). A bit more discussion about the origins of kinetic vs thermodynamic control.

Taxol

Your energies look nice, but your "more stable conformation of 9" is in fact a different molecule with different stereochemistry. You should have spotted this! Did you find any more conformations? Twist boats? Other chairs? ("which we should be aware of.") Hyperstability? Any extra calculations (heats of hydrogenation) you could have done?

Taxol NMR

Your tables have no numbers so I cannot reference them directly. The 13C is presented i a way that makes comparison difficult. Perhaps plotting the error rather than the shift would enable big errors to be spotted more easily? Could the analysis change if you tried other conformations of 17? Do you have any statistical measure of the quality of the fit? (RMS deviation?)

Epoxides

= X-ray structures

There are three anomeric centres in the structure, but you only analyse one of them. One of the others is in fact far more interesting. Good discussion for the Jacobsen

NMR of epoxides

You just present plots, but in truth since you do not quote any experimental values I do not know if your spectra are accurate. You do have to find the expt values from the literature.

Absolute configuration

There are in fact many literature values for both epoxides; you quote only the ones that agree with your calculations! there are others that do not, and you should discuss this.

Are there any VCD lit values for these epoxides?

TS

Your results are very terse. You mention that you used the lowest energy TS, but which one is this? Discuss the geometry of the lowest? Does it have any of the features you might have spotted in the x-ray structures? More detail needed here


NCI and QTAIM

Some nice analysis here for the NCI, but the QTAIM needs to be a little more specific about where the BCP points occur

New candidate

" I believe it is commercially available,"  ? Is it? and what is its price?

Overall, pretty good, but more attention to detail is needed for a better mark.