[ben809]

Hi I was just wondering if anyone has an idea of how I can tell from the GC images I've posted which diastereomers have eluted from the GC (one is from MCPBA and other H202).

Can you also tell from an HNMR??

Thank You

[Dan]

Hi I was just wondering if anyone has an idea of how I can tell from the GC images I've posted which diastereomers have eluted from the GC

In short, you can't for sure. What this tells you is that the mCPBA reaction has given two major products, and the peroxide has given one major product. Furthermore, the three products are all different (since they all have different retention times), so there is a regioselectivity question as well as diastereoselctivity.

NMR can be used to determine regioselectivity  quite easily. Diasteroselectivity can also be determined by NMR , but would most likely require the use of more complicated NMR experiments such as NOESY and ROESY NMR.