Alfa Aesar, we need to talk. You haven’t been giving me what I need, so I think it’s time I found somebody else.
My carbon tetrabromide stock fell low, and that’s when you fell into my life. Drawn to you by your fair prices, and impressed by your quick shipping, I would never have thought you to be such a source of aggravation later on.
Two steps after using the carbon tetrabromide, I ran into issues. Reactions not reacting how they should. At first, I thought it was me: impure products, glassware not dried thoroughly enough, bad luck. Back tracking through the reactions, I still couldn’t find the source of the problem, not even thinking about the CBr4, because “Oh, it’s new, it should be fine.” It was not.
The last thing I could have possibly checked in the reaction was your “fresh” CBr4. I… I should have told you before, but I got some from Aldrich instead. It was better. Turns out, your weird CBr4 gave me some kind of dimer. It went undiagnosed for a little bit, hence the cause of my frustration, but you might want to get that checked out. Yeah, so we’re like, over.
Corey-Fuchs-ing someone else
-Chiral Jones
Chiral Jones 
you can sublime CBr4 under vacuum with a heat gun from a round bottom into a long reflux condenser and then wash it out with solvent and rotovap it down. that always worked quickly and well for me.
You know, once I figured out the Alfa CBr4 was “bad” for Corey Fuchs reactions, I just used more of the borrowed Aldrich stuff from a different lab (on a pretty big scale), because I knew it worked. After using what I felt was a comfortable amount to borrow, I looked into purifying the Alfa stuff, in case I had to push a lot more material through. I found the sublimation method, but I couldn’t find the bottle of Alfa CBr4. Perhaps it met its demise in an Appel reaction somewhere…