maxscorpio (Stranger)
05-25-03 08:33
No 435321
      safrole isomerization  Bookmark   

In the isomerization of safrole, KOH is the prefered catalyst. Can NaOH be safely substituted?   AND if the reaction is not carried out under vacuum, the water liberated interferes. for this, calcium oxide is normally used which reacts with the water forming an insoluble. CAN calcium oxide be substituted with magnesium oxide or some other chemical?     any suggestions appreciated.
(PVC-Analog Taste-Tester)
05-25-03 10:31
No 435351
      Yes..  Bookmark   

Yes, NaOH can be used, but supposedly the yield of propenylbenzene will be lower - Don't worry about that. Also calcium oxide is well worth investing in(No excuses, it's easy to get). Be sure that you dry your parsley seed, sassy, or whatever oil with baked epsom salts before isomerization..Peace!cool

  Btw, if you're refluxing it under normal pressure, without a vacuum, add some boiling stones or crushed glass to prevent bumping or splattering..

Love my country, fear my government.
05-25-03 10:49
No 435355
      Actually it doesn't bump at all when doing at...  Bookmark   

Actually it doesn't bump at all when doing at atm pressure,boiling stones are not needed.And don't use NaOH,it's weaker base and yields will be low or close to nothing,does the price of KOH really outweigh the cost of lost safrole due lower yields?You might also want to check out this:
Post 431957 (raffike: "CaO/KOH isomerizing procedure is nicely scaleable", Methods Discourse)
05-25-03 11:26
No 435359
      Boiling stones...  Bookmark   

While the distillation may not appear to bump, it's still good practice - and generally a good idea - to use boiling stones for something like that.  It's not like they're a problem to get, and they may well save a headache if it does for some reason think about bumping.  Bumping can be an amazingly depressing experience - all reasonable precautions should be taken to avoid it if possible.