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cyclopentadiene

Good results. Nice referencing (3) which shows you have done your research. Any detail on lowered by the secondary orbital interactions available in the endo approach?

Taxol

You report one chair for each of 9 and 10. There are two of course. How do you know the one you found is the lower of these two?

NMR

After optimising the geometry in Avogadro, a Gaussian Checkpoint File ? Are you sure? I think you sent a Gaussian input file? and you should note that the geometry was re-optimized (perhaps it was not?).

Excellent 13C match, but presentation could be improved by a bar chart of the differences? Normally quote Gaussian energies in hartree, not kJ!

Bit of a problem however. Your dithio derivative has a boat conformation. Did you try either of the two chairs to see if they were lower? It is rather odd, because as it happens, the 13C for boat is actually a better match to expt! So the real molecule may well be a boat. But you have to put more effort into proving that it is NOT chair.

Epoxides

Xray

Shi catalyst, well done for identifying all three anomeric centres. One of them has a big difference in C-O lengths. You really need to focus on this one and really explain it by identifying the orientation of the "lone pairs". Any idea how they can be approximated?

Rotations

First, the NMR. Did you think of calculating the couplings (after all, you anticipate measuring them shortly)?

Bit worried about the two lit values (-39 and +129). You need to pick up on this anomaly? A comparison to literature suggests that the calculations did not run correctly. . Yup, that is true. But you really need to think about what might have gone wrong here. Did you for example fully optimise the geometry using QM? Are the rotations of the phenyl groups odd? Lots of things to ponder.

TS Energies

Good analysis. You spotted that only the lowest of the four TS needs to be considered. Not many did!

QTAIM and NCI

Excellent, full of nice detail.

Suggested epoxide

Why did you suggest it. Are the starting materials commercially available?

Overall, very good!