Talk:Mod:jp806organic

1.1 Your structures 1 and 2 are both exo (enantiomers of each other!) 2 should be endo, and have the higher energy. What orbital interactions favour the endo D-A product? 3 and 4 are fine. Where is the "extra" bend energy in the structure of 3?

1.2 Your energy for 5 seems OK, although you haven't given a structure for the lowest energy conf. Good discussion of "odd" structures! The structure labelled 6 is actually 5, and has a non-planar carbonyl group, hence its high energy! In your second structure 7, you've actually "flipped" to the other enantiomer, which may be why the "up" and "down" are more similar in energy than they should be.

1.3 Looks to me like you've modelled diastereomers of the compounds in the question - the protons at the ring junction should be on the same side as the CMe2 unit, whereas yours are opposite. Otherwise the structures look OK!

1.4 All your structures have boat conformations in one of the rings! This is a complex question - it looks to us like one would need to model the tetrahedral intermediates rather than the ground state confs in any case.

1.5 Fine!

Mini-project Click project - Did you try any other confs for each isomer? Would be good to try to quantify how good the correlation is for each case (see the provided lit refs to the 13C prediction method).

Largazole (nice name!) - there are 16 configurations, not conformations! The (+)- and (-)- forms suggests you're looking at enantiomers. These would have the same energy (in an achiral environment) and the same 1H, 13C spectra etc. So it's not clear why you would compare their spectra... The rotation calc (should be opposite and equal for the two enantiomers if you use the same conformation of each) will be interesting.