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Talk:Mod:XJB36170329

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Cyclopentadiene

Good results. A bit more discussion of kinetic vs thermodynamic control? Transition states and orbital explanations?

Taxol

Good results, but there are other conformations? Two chairs for both 9 nd 10 for example, as well as twist boats? Did you locate any of these other isomers?

A bit of discussion about hyperstable olefins?

NMR

Good results, but you should not quote chemical shifts to so many decimal places, ie 2.015871525 and it is difficult to see, from the way you have set out your results, how well the spectra match with calculation.Your analysis "he comparison of the computational NMR and the literature assigned NMR is fairly good" is rather vague, and not very quantitative.

Epoxides

X-ray structure

You identify the anomeric effects, but you do not really explain why the lengths are similar for two pairs, but quite different for the third. A little more about the steric effects in the Jacobsen catalyst was needed.

NMR

There is no analysis, or comparison with experiment for this section.

OR

You quote literature values but you do not discuss why the values are apparently quite different. similarly, you compute rotations for both enantiomers, but do not discuss why the values for a pair of enantiomers are actually quite different again. More understanding of what is going on here is needed.

TS

Your Table 14 is not correctly analysed. You appear to have averaged the energies, and then quote a difference in ΔG of -14351 kJ? This is then converted to a difference in concentrations K of 327? These values make little sense. Have you used the correct units? What molecule is Table 14 referring to? The configurations RR or SS do not correspond to trans β-methyl styrene for example.

QTAIM and NCI

Very little critical analysis here.

Proposal

" The alkene is shown available for lab use" Could you quote eg the catalogue number, and perhaps even the cost?


Overall, I think you need to put more critical analysis and understanding into your reports.