Talk:Mod:Andy1234

1.1.1 The energies are good and discussion is spot on. The contribution to energies of the hydrogenation products is particularly well presented.

1.1.2 Structures and nergies are good and the discussed optimisation procedure is easy to follow. The reason for stereocontrol is correctly identified. MM2 cannot identify Grignard reagents because the atom types are not familiar as you said; you may be aware that it is in fact possible to manually input the required parameters into Chem3D so that the magnesium can be tolerated.

1.1.3 The full conformational analysis employed ensured that you found the right structures and hence correct energies. The definition for a hyperstable alkene is correct; although you can’t strictly compare the energies of the alkene vs. the alkane using MM2, I agree that it demonstrates the instability of the hydrogenated form.

1.1.4 The optimisation and analysis of reactivity is very thorough. I particularly enjoyed the comment “It appears that the authors have not considered rotating the ethylamido group round the α-carbon”! As well as the transition states, it may also prove fruitful to calculate the energies of the intermediates formed (although I didn’t find this to make the answer any clearer myself).

1.1.5 The MO diagrams are well presented and discussed as are the relevant IR stretches. Reslt from the AIM analysis is interesting; I have recently stumbled across a few papers invoking hydrogen bonding between certain CH and C=C groups. Good discussion of the pros and cons of higher level calculations.

MP The presentation of the experimental vs. calculated NMR shifts is excellent. The reaction was clearly a good choice given the results (in spite of the flexible alkyl chain). It is a shame that the data for the other isomers wasn’t reported.