5-mapdb

[adder]

Still it's much more stable than regular acetals, lone pairs on oxygen atoms extend the aromatic system giving the structure increased stability despite the methylene unit kind of breaking the conjugation (methylenedioxybenzene fulfills Huckel's 4n+2 rule with each of oxygen atoms donating one lone pair to the system). One would need a pretty strong Lewis acid to coordinate the oxygen atom lone pair and a nucleophile to attack the methylene moiety to open it or a very strong nucleophile alone with additional electron-withdrawing group(s) on the benzene ring (edit: from what I've found on this the conditions for the ring opening are pretty forcing too!). I don't think MDMA or MDA breaks down to any extent in stomach.

 

[Limpet_Chicken]

Yes. I did not intend to imply it did so. More that it doesn't like things like sulfuric acid. Just don't drink any concentrated sulfuric, HI, HBr whilst rolling and things should look a lot better