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Talk:Mod:xy307

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Cp: Structures and energies are fine. Why is the torsional energy lower for 1? Why is 2 kinetically preferred?

NAD: Structure 6 is fine. Did you try to find any more conformers for 7? There should be a lower energy one...

Taxol: Your structure 9 has the 6-ring in a boat-like conformation. Your 10 is a wrong diastereomer - it has the CMe2 "trans" to the hydrogens at the 6-ring junction, when it should be "cis". What exactly causes the strain if the alkene were to react?

CCl2: Orbitals look OK. How exactly do they explain the difference in C=C stretching frequencies?

Mini-project: Quite a nice choice of project. However, your Jmol of II shows a problem - the alkene bond angles are crazy! It's a shame you didn't spot that - it would explain why the predicted 13C shifts for the alkene are so far out! You should have attempted a quantitative comparison of the calculated and experimental data, and between the two isomers. Not sure what you expected to see from the IR - it would not be likely to allow you to distinguish the isomers, which was the point of the exercise. How WOULD you tell them apart? In general, you haven't shown any chemical reasoning/thinking - you have simply done the calculations!