View source for User talk:St908(module 1)

Put your name at the top, in the manner of a scientific article!

= Cyclopentadiene =

good results, but a little more discussion of kinetic vs thermodynamic control is needed, + explanation of why the dimerisation is the first, and hydrogenation the second.

= Prolinol =

What  IS the angle of deviation between β-H and C=O. You really should report its actual value, and not merely as a slight distortion.  How does this change when you replace  MM2 with PM6?
The same is true for molecule  7.  You mention an X-ray structure for  7?  Is that ref 2? I could not find the article reference in your report.  If there is an  X-ray,  you could include that structure in your report together with a quantitative comparison with your calculated structures.

= Taxol =

In your model, the stereochemistry of the alkene is wrong, and the rhs 6-ring is boat rather than chair. Hence your energy for both components  is quite high. Take a little more care in constructing the correct model.

= Carbene =

There is no real need to report the  MM2 results; this experiment is really a molecular orbital technique.  You note the geometry is distorted, but can you describe a little more how?

I think your  MOs are distorted (there is a random bug in the MOPAC program unfortunately which causes this), but you should at least notice that the MOs should show a plane of symmetry passing through the  C-Cl bond and the mid points of the alkene, which your  MOs do not have.  You should try to identify when the bug occurs by trying to calculate the  MOs using another program such as Gaussian.  Programs  DO have bugs,and you  DO have to learn how to cope with them.

You did well in reporting eg bond lengths (surprising how few people do!)  Did you manage to track down the  C-Cl  IR stretches? They too (and their lengths) also show something interesting

= Mini Project =

Missing?