First attempt at benzaldehyde via DMSO/HBR..
I decided WTF and gave it a shot.
4 16 oz bottles of DMSO
150ml of crude HBr
500ml of Benzyl alcohol
Added the DMSO to a 3L flask set in an oil bath and proceeded to heat the oil bath to about 60C. Then 500ml of benzaldehyde was added followed by the
HBr and heated to 100C.
The reaction sat for about 3 hours at 100C with no visible reflux of dimethyl sulfide nor much of a cabbage smell or cherry smell.
I said fuck this damn reaction is broken/going to slow, I'm taking this bitch to reflux and proceeded to heat the oil bath to 140C. After about 30
minutes the reaction began to reflux with gently boiling. Curious to know what the temp was of the reflux I set it up for simple distillation.
Whatever is distilling is coming over at anywhere between 85-95C and the temp is going up and down.
OK thats weird.
Dimethyl sulfide has a boiling point of 37, HBr 125, dimethyl disulfide 109, water 100C and benzaldehyde at 179C(?) and DMSO at 189C(?).
The distillate is coming over in a bi layer as well so who knows what the hell it is... probably some combination of water/HBr/DMS. Will have to
fractionate it later to figure out what the hell it is.
So, after about an hour and a half, I have managed to collect about 300ml of something, with the upper layer being in greater proportion to the lower.
The temp of the distillate is running about 95 degrees as of now.
The good news is the inside of the flask is now taking on a definate strong cherry scent with an acid kick. 
I plan on continuing to reflux this until it stops coming over or I catch about 400ml or so of the upper layer stuff. I figure if it takes one mole of
DMSO to oxidize 1 mole of benzyl alcohol, so that would be about right for 100% conversion.
Update in a couple hours...
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