synthesys (Stranger)
05-02-03 22:35
No 430930
      DMF/O2 wacker question?  Bookmark   

Can one damage the ketone molecule by washing it with the sodium bicarbonate solution, after hydrolizing it with dilute HCL?

I mean, I know the answer is no, but a Freaky thing is happening to me on the last wacker.

The catalyst was prestirred for 7 hours. The ratio of product/solvent/pd/copper was 100/200/1/5 . The wacker took longer than usual to cease absorbtion, 30% more time. Swim distilled the ketone without washing it.  Hydrolized it, separated it, distilled it and it came over 23-26 degrees higher than the starting material. Looked and smelled great. On the bisulfate test it gave me chicken greese after sitting overnight in the freezer, instead of the crystals. So it's an impure ketone, thought Swim. So swim washed it with dilute HCL, then sodium bicarbonate, then brine. Did teh bisulfate test again.
Solid crystalslaugh Great, thought swim as he headed for the rotorvap... Well, at about 150 C swim stopped that processshockedshockedshockedshocked My saf comes over at 100C. It's hot where I am, so going above 150C in a small room is not much fun. I just stopped.

Seek and you shall find