I saw a smart, sexy woman run a peracetic oxidation as normal on excellent quality iso, to get a usual yield of glycol, then she did the pinacol rearrangement as usual with 15% H2SO4 w/methanol for 2.5hrs. She distilled, keeping 270-300C. She tested with bisulfite, and it was chicken fat, some ketone but piss poor yield. I recommended she redistill keeping 280-290C (BP of ketone is ~286C). Ok, the yield is low for her, but she hope it's better ketone. I encouraged her to test again with bisulfite, and it was still forming globules of slimey crystals.
Starting to doubt the validity of the bisulfite test, perhaps the bisulfite was old or something, (the test was 5ml sat aq. bisulfite w/.3ml ketone shaken in a test tube), I decide to recommend that she aminate anyways. Well, the bisulfite test was right as usual. It's funny how something that takes 1hr to test, can save so much headache later. In the end, she got like 2.5g from ~20g suspected ketone.
I'm pretty sure this is the result of either too little stirring or bad hydrogen peroxide in a peracid technique... but... I'm wondering if others have seen something that's like ketone come over at the right temperature and not be ketone.
I think because she used a new brand of H2O2, or that stirring was less than optimal, that the oxidation never happened. But what was the fraction that came over at the temperature of ketone? MDP2Pol?
Does anyone have any really, super, great, easy ways to titrate peracetic acid and/or H2O2 with nothing but otc chems?