[g-bones]

Hey guys,

I am working on the mechanism of this acid catalyzed rearrangement and its giving me a tough time.  Anybody have any suggestions.  in step A I opened the epoxide to yield the more stable carbocation and then did an alkyl shift in a pinacol type movement.  From here I am having trouble shifting the other alkyl groups.  should I start somewhere else? any tips would be appreciated! thanks!

[aldoxime_amine]

I am not sure how to explain the rearrangement but I have attached it anyway.

Note that there is no carbocation formation during cleavage of epoxide by acid, even though it is SN1.

[g-bones]

thank you for your *delete me* clever mechanism....

[aldoxime_amine]

An observation: Since attack at the epoxide is strictly anti by the alkyl group, had the bridge been into the plane no rearrangement would have occured.

[Squirmy]

Why wouldn't that just change the alkyl group that migrates?