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Safrole Isomerization Review

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Rhodium:
Other than the first route, the other methods aren't ranked in a special order.

http://rhodium.lycaeum.org

psychokitty:
The biphasic NaOH-water-toluene-alkene-PTC-stirred-under-80-deg-C reaction does not work on isosaf_ole.  SWIM tried this reaction by the book but stirred and heated for 12 hours!!!  The oil so obtained was assumed to be the real McCoy and used in a modified performic reaction.  End product from 100 g of suspected isosaf_ole?:  85 g of saf_ole and some tar.  No ketone of ANY kind which lends proof that the modified performic only works well on isoalkenes.  Anyway, the saf_ole was then isomerized as per usual under anhydrous conditions using reduced amounts of PTC and KOH stirred between 80-120 deg C for about 15  minutes.  Yield: about 90% isosaf_ole, which when used in a modified performic reaction, yielded 55% of the ketone, which when used (25 g) in a nitro-Al reductive amination, yielded 16 g of desired amine HCl.

--PK

Osmium:
> Comments? Additions?

In the vac reflux isomerisation it says don't use more than 800ml in a 1L flask. That's wrong.

1.) For 800-1000ml use a 2L flask
2.) Bigger reactions than that have the tendency to bump violently, apparently magnetic stirring isn't good enough anymore.

(For our industrially oriented bees: using a capillary to introduce a stream of air bubbles, comparable to good oldfashioned vacuum distillation should work to circumvent the batch size limitation).

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