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good introduction. Nicely presented.

Cyclopentadiene

eco product An interesting concept! stretching, bending, torsional and Van der Waals contributions to the energy But one of these is larger than the others? Discuss!

The orbital diagram you include is relevant but it needs more? It is not entirely obvious from just this one diagram what is meant.

Taxol

Good results, but your optimised structure for A is a trans ring, it should of course be cis! Oops!

I do like your investigation of hydrogenation! Well done.

NMR

Your conformations for C and D are both boats? Having discussed the chair in the preceding expt, why did you suddenly accept a boat as your model? This indicate the conformation is wrong in this region. Could you not follow that up? Did you check the chairs as well? Maybe this is why your mean 13C errors are ~5ppm? (well presented though). A Look at Thermodynamic Properties? This shows D is lower than C, but why do you mention A below that?

Epoxides

X-ray

At the anomeric centre But which one? There are three! Bit more analysis needed here.

Again, just a little more analysis of the Jacobsen catalyst.

NMR

Good results. Did you think of calculating the couplings (easy for such a small molecule)?

The most significant deviations are found in the aromatic ring Yes, that is worrying. The discrepancy should be smaller. suggesting that the configuration is wrong Again, did you follow up this observation?

Rotationsl

Oh dear. Lit value for ® is -33.3 (only one? There at lots of lit values! Quote the range, not the one that agrees best with your calculation!) but you quote +30.6 for the calculation; however with an opposite sign in the case of styrene oxide. . So how does this statement follow: Hence the computed enantiomers have the following absolute configurations: (R)-(+)-styrene oxide ? You do not state whether your own calculation was for R or for S? This is crucial to the entire experiment! You missed an opportunity here to really get to grips with the expt.

Absolutely no need to quote all those energies below. You dont use any of them except the last? So just quote the last! Not sure what y ou are doing in the table entitled Enantiomeric excesses determination? You need to establish the lowest R and the lowest S TS, and calculate the ee just between that pair, ie one single value. You report four such values, which suggests you have not thought it through to its simplest form.

NCI

No discussion here for any of the last three topics. I guess you ran out of time. After a very good start to the expt!