Dr_Heckyll (Hive Bee)
08-03-02 20:25
No 340858
      Sensitivity of methylenedioxy group  Bookmark   

How sensitive is the methylenedioxy group in a simple molecule like methylenedioxybenzene to acid-catalyzed splitting? Will it be split by methanesulfonic acid or acetic acid in a water-free system and prolonged reflux?

Happiness, health and wealth through chemistry...
(Hive Addict)
08-04-02 10:06
No 341206
      naaa don't think so. HI(aq) will do BF3 will also ...  Bookmark   

naaa don't think so.
HI(aq) will do BF3 will also (or most other lewis acids)
(Hive Bee)
08-04-02 19:10
No 341415
      Re: Sensitivity of methylenedioxy group  Bookmark   

On a similar note, relating to my current project;

What would be the effects of ozonolysis on a methylenedioxy benzene? Assuming of course the standard controlled conditions are met, the benzene ring is not attacked, and that a dilute O3/O2 mixture is used?  Would the methylenedioxy group even make a difference from the results of an ozonolysis on plain ol' benzene?  This may seem obscure but to me it is quite pertinent.
(Hive Bee)
08-04-02 19:51
No 341436
      By instinct rather than by knowledge I would be ...  Bookmark   

By instinct rather than by knowledge I would be worried that the product would be something like

Molecule: bdo ("O=C2OC1=CC=CC=C1O2")

Happiness, health and wealth through chemistry...
(Hive Prodigy)
08-04-02 19:53
No 341438
      Unstable  Bookmark   

This compound is an acid anhydride of carbinic acid and catechol, and would likely hydrolyze in moisture to carbon dioxide and catchol, would it not?
(Hive Bee)
08-04-02 20:10
No 341444
      please forgive my ignorance  Bookmark   

How exactly would O3 attack the methylenedioxy to form this compound which hydrolyses to CO2 and bezenediol?
(Hive Prodigy)
08-04-02 20:19
No 341447
      It Doesn't  Bookmark   

That compound would not be formed.
(Wizard Master)
08-07-02 18:18
No 342754
      Halogenating Reagents  Bookmark   

Halogenating Reagents: PCl3 or PCl5, PBr3 etc... will halogenate the methylenedioxy ring with halogens.

Reference? Must find it again? Stay tuned!

(Chief Bee)
08-07-02 19:27
No 342790
      methylenedioxy ring chlorination  Bookmark   

It's in http://www.orgsyn.org/orgsyn/prep.asp?prep=cv2p0549
(Wizard Master)
08-09-02 19:05
No 343750
      Thanks Rhodium!  Bookmark   

Ahh, yes! That's one. There is also another, in the JOC, I think??
(Official Hive Translator)
08-25-02 09:06
No 348848
      Ozonolysis  Bookmark   

There was a ref (on the Hive? i think) that described ozonolysis of piperic acid to piperonal - so i think it's not much of a problem, of course having the exact conditions at hand is strongly recommended.

(Hive Bee)
08-25-02 09:51
No 348857
      ozon etc  Bookmark   

As far as SWiM remembers, O3 is active on olefins as isosafrol, where it oxidizes the propenyl pi-bond and converts the propenylbenzene analogue to its benzaldehyde derivative (i.e. isosafrole -> piperonal).
Stability of the methylenedioxybridge: be sure to keep it away from Lewis bases as AlX3 (X=Cl, Br, I) and all those other stuff that can be used for the O-demethylation of methoxybenzene derivatives (such as vanillin, isoeugenol etc). Don't have the exact references and patents handy, but SWiM remembers they are used for the synthesis of 3,4-dimethoxybenzaldehyde and 3,4-dimethoxyphenylpropene from piperonal and (iso)safrole respectively.

Doped(TM) since 19.... euhm... a long time smile