[AlphaScent]

Has anyone ever had trouble reducing the ozonide?  As in the reaction is quite sluggish?

I was taking methyl-2-methyloct-5-enoate and trying to get the aldehyde.  It took 75 eq of DMS and 26 days to reduce to aldehyde.  Crazy, Right!!

There has to be some sort of intramolecular interactions that are hindering the attack of DMS.

[rolnor]

Sometimes its slower but for me it has taken hours, not days. I have used DMS and also iodide. I guess its faster if you heat it but thats a problem with volatile DMS? I have worked a lot with ozonolysis, also built my own ozon-generator from an old x-ray transformer and a Liebigs condenser, it worked fine, good memories!

[AlphaScent]

Well that's cool you built one!!

I just did the same reaction on the isopropyl ester and it worked great.  5 eq DMS added at -78, stir for 30 min.  Then let warm to RT.

I think I want to prove that there is a quasi 6 membered ring of some sort between the ozonide and methyl ester hindering addition of DMS.  The isopropyl ester mitigates this interaction.

NOESY could be useful.

[rolnor]

Interesting, molecular modelling could also be useful.