The_Davster - 26-7-2007 at 15:53
Easy question for those in the know, I have never had to do any of these before. At work I want to do a reaction for which I need to use the oxime of
a fluorenone compound, I know how I will do that reaction, but in researching the making of the oxime I am finding conflicting info. I have used
scifinder, and found hundreds of methods for oxime formation, but is there a specific one which is preferable for the substrate? I can't just screw
around and try things as the fluorenone compound is ~250$ for 5g(our group has a huge budget it seems, ordering 200 dollar chemicals are common
)
Would it be as simple as dissolving the fluorenone compound in EtOH(which it is soluble in) adding a stoichiometric(?, or excess?) ammount of
hydroxylamine HCl, and then some(catalytic? or a molar equivalent?) NaOH, letting it sit for a few hours and then working it up somehow?
Any help is appreciated, I am pretty new to organic synthesis of previously unknown organic compounds.
Ozone - 26-7-2007 at 20:14
Seems like it should go quite nicely in DMSO or, maybe, DMF. I have had luck with oximation of carbohydrates (aldose and ketose) in pyridine (also
your base) at rt. Steric bulk might kill the kinetics, so some heating may be required. Try to keep it all anhydrous as elimination of water drives
this reaction. Excess hydroxylamine (to a point) should also favor product (but may complicate workup).
Cheers,
O3
[Edited on 26-7-2007 by Ozone]
kmno4 - 27-7-2007 at 06:33
Two standard procedures found on Berichte and Journal of Organic Chemistry (for fluorenone).
I think there is no problem with little modifications (Na2CO3 instead BaCO3 etc.).
Propably procedure for benzophenone oxime described in OS is also convenient for fluorenone.
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The_Davster - 28-7-2007 at 16:45
Thanks! I had been looking at analogous procedures for benzaldehyde and acetophenone, but benzophenone had completly slipped my mind...so much more
similar!