01-13-04 03:30
No 482166
I can't BELIEVE this.. I copied the data into the working notes w/ 5% NaoH rather than 5% sodium bicarbonate to neutralize the acid after the DH20 washes on a performic reaction. Everything was perfect until then. Immediately the aqueous layer went reddish brown and the bottom dcm looked like coffe w/ milk in it. I immediately dumped in some 15% H2SO4 to reverse the pH and now I have some OJ colored layer on top of the dcm and yellow/coffe underneath. After about 10 min the top oj layer is yellowish brown and the bottom dcm layer is still milky but more brownish green.
The NaoH was 4 gms in 150 mls DH20. H2S04 was 20 ml conc in 220 mls DH20
Have I screwed everything up, or can I still recover from this?? Please help asap! ( side reactions are looming!)
Infinite Radiant Light - THKRA
(LinguisticBee)
01-13-04 18:20
No 482275
nothing is fucked up, at all. An NaOH wash will simply extract different impurities than a mildler alkali, it will not hurt your ketone, just wash w/ H2O a couple times before you distill and you are good to go
We are all just witnesses.
(Hive Addict)
01-13-04 19:01
No 482285
Thanks antibody... I ran a tlc plate ( posts coming when I get done) of the MeOH/H2SO4 completion stage product, one of the NaOH aqueous layer, and one of the DCM layer after I added the 15% H2SO4 to recover from the NaOH addition.
The plate showed exactly the same spot sequence before/after and nothing in the Water/alkali layer. Based on that info, I took a deep breath and appreciate your time posting a reply! Thx for the confirmation!
Infinite Radiant Light - THKRA
(Chief Bee)
01-13-04 19:20
No 482290
NaOH is actually an option, but with a bit lower yield: ../rhodium /peracid
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