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How Not to Do It

How Not to Do It: Bromine

I wasn’t an eyewitness to this one, although I wish I had been. I pass it on secondhard from a former colleague of mine, on which it made an understandable impression.
Bromine’s an odd element. The two lighter halogens leading up to it are nasty gases. Fluorine, the first one, is actually beyond merely nasty, being a hazard to life from several different directions. Chlorine is something you can handle,although it was still nice enough to be used on the battlefield in World War I. But bromine is the first one of the series that makes the grade as a liquid at room temperature and pressure.
All the halogens have colors – for example, I’m told that liquid fluorine is green, not that I hope to see any of the damned stuff, and liquid chlorine is supposed to be yellow. Iodine is notoriously purple, and For its part bromine is a deep, almost opaque red-orange. It’s one of those liquids that hasn’t forgotten its gaseous heritage, and you always see it with a red haze of vapor above it. It’s unmistakeable.
You’d think. Our story begins, as do so many fine lab disaster tales, with the phrase “There was this summer student. . .” In this case, there was this summer student whose grad-student supervisor thought he was ready for a spot of bromine work. They’d ordered a fresh bottle, which had come in from Aldrich the day before, and everything was ready for a good old-fashioned bromination reaction. As the chemists here know well, if you add bromine to a compound with an exposed carbon-carbon double bond, it’ll react with the alkene, breaking it down to a single bond with a bromine on each carbon. Sometimes it’s fast enough that you can see the red color disappear as the stuff drops into the reaction, and you can just go until the color persists, but sometimes it hangs around as an orange solution for a while.
So, our grad student leaves for lunch, entrusting this small-scale bromination to his ready-to-solo summer undergrad. And he wanders back presently to check out the reaction, but there’s something wrong. The flask has no color to it, for one thing. For another, there are chunks of floating crud whirling around in the clear solution, and that’s not right, either. He turns to the summer student and asks him if that’s the bromination.
“Sure is!” Hmmm. Did he, in fact, use. . .bromine in this reaction? Oh yes, indeed. The bromine that just came in? Absolutely! What’s that stuff floating around in the flask? Well. . .the bromine, right? Show me this bromine, then, by all means. And the summer student goes over to the opened shipment and lifts out the vermiculite packing material that’s in there to keep the bottle from breaking during shipment. Behold the bromine!
No, you cannot make anything foolproof. Fools are too tricky. Needless to say, anyone who can’t tell the difference between bromine and box-filler is someone that you don’t want within a hundred yards of a working research lab. My colleague had not recorded the reaction of the grad student to this revealing answer, but I’m sure it involved raised voices and plenty of adjectives.

21 comments on “How Not to Do It: Bromine”

  1. Harry says:

    I laughed out loud at this story. At least the vermiculite wouldn’t ruin the substrate they were trying to brominate. In my experience- when you mix up materials, Murphy’s Law kicks in and you find that whatever you mistakenly used reacted with the most expensive and/or difficult to make material in your project in such a way as to make it totally unrecoverable.
    Also- Chlorine is a yellow-green liquid. I had the “pleasure” of running a chlorination where I had to reflux the chlorine using a cold finger condenser full of dry ice/ acetone. It was fascinating (if a bit unnerving) to watch liquid chlorine merrily refluxing.

  2. Fun with Bromine

    Every so often, Derek Lowe will write about some 'incident' in the lab. Today, he talks about a Bromination that didn't happen as planned: How Not to Do It: BromineI wasn't an eyewitness to this one, although I wish I…

  3. schinderhannes says:

    I head nearly the exact same thing happen to me as well! Only this time the undergrad thought the vermiculite was nBuLi. (A solid beeing a 1.6 molar solution in Hexanes…) Well stupidity is really endless! To top it of this idiot had used n-BuLi under my supervison a week before and forgotten what it was….

  4. Jeff Bonwick says:

    Bromine — that’s a gas. 😉 Early on I thought you were going somewhere else entirely — I imagined someone confusing the red-orange bromine halo with the red-brown fuming nitric acid halo. But then it’s not at all clear which story would end worse.

  5. Derek Lowe says:

    Yep, fuming nitric acid is about the only thing that I could imagine confusing with bromine. And I’m with you – I’m not sure which one you could cause the bigger disaster with. I have a short nitric acid story that’ll make another installment in this series at some point. . .

  6. Philip says:

    I’ve heard this story before. Many times. In fact, I first heard it about 25 years ago. I wonder if it’s not the chemists’ version of the “Poodle in the Microwave” story, our little urban legend (myth?). What’s odd is that it’s always been with bromine, although one commenter has heard it with butyl lithium. However, it is a good opportunity to describe the halogens and educate the nonchemists among your readers.

  7. Don Butler says:

    Derek:
    I saw this reaction run by a B.S. chemist in my lab decades ago. After that I always mentioned that the reagent was in a bottle packed with vermiculite as a filler between the carton & the bottle. I can also vouch for the colors of the elements that you mentioned.
    Don Butler

  8. Anonymous says:

    I had the pleasure of doing a Hunsdiecker reaction ages ago- refluxing bromine in CCl4, with a 100 W light bulb irradiating the flask. Refluxing bromine is a very, very spooky thing- behold! Liquid death and dismemberment!

  9. milo says:

    I was teaching a lab once where the students needed to use some dry benzene. I had set some up to dry the night before using 4A sieves. During the lab a student came by and told me that the beneze was frozen. I went to the students station and saw that they had a stoppered, N2 purged 25 mL round bottom that was filled with sieves.

  10. Derek Lowe says:

    Philip, I’ve had other people tell me this one, too, but my colleague vouched for it herself. And there seem to be other eyewitnesses to similar mistakes (see the other comments). I think that it’s partly an urban legend, but one that gets renewed, with several nucleation sites, by new generations of clueless undergrads.

  11. Mark McPhee says:

    I first saw that story in Professor Huheey’s excellent tome on Inorganic Chemistry. It provided great comic relief while cramming space group data and other fun inorg. material.

  12. Still Scared of Dinosaurs says:

    I admit to having no qualifications to comment on the rules of running a lab, but can anyone explain the humor in putting young people in such a potentially dangerous situation and leaving? Two statements from the story:
    >> Our story begins, as do so many fine lab disaster tales, with the phrase “There was this summer student. . .”
    >> Needless to say, anyone who can’t tell the difference between bromine and box-filler is someone that you don’t want within a hundred yards of a working research lab.
    Sounds like a clear failing along the chain of command from the summer student to the grad student to the person in charge of the lab that includes any retelling of the story that doesn’t end with the words, “…and I’ve made damn sure nothing like this will ever happen in my lab!”

  13. I must admit I’ve never heard this one before. Wow.
    The only thing I have that comes close, unfortunately I’m foggy on the details. It was undergrad organic chem lab. The reaction involved 1M iodine. For some reason there was also a 16M bottle of iodine in the room. Needless to say, college students to not double-check or read properly. I was merrily slaving away when a purple cloud floated past my face(!) from the student beside me. She hadn’t been paying attention. Shortly thereafter the entire group was notified to please be more careful. At least five others had done the same thing.

  14. burt says:

    It’s easy to be flip about this, but if, instead of using the vermiculite, the student had poured out te REAL bromine without gloves– well let me just tell you, you do NOT want a bromine burn. I think the grad student should not have entrusted a newbie with a highly nasty substance like bromine.

  15. PJ says:

    This tale is humorous because no one was hurt and every chemist who reads this can relate to it. It is kind of like the tale of a first year student who extracts (or tries to) water with acetone.
    However, I have seen a few accidents in academic labs that have resulted in very severe injuries. These accidents were 100% avoidable, if the person was properly trained and the basic rules of laboratory safety were followed. Unfortunately, academic labs are notoriously dangerous places to work. It is only when someone is taken away in an ambulance that the university/department decides to remind the PIs of their responsibility for insuring a safe environment and adequate training for all researchers in their lab.

  16. JSinger says:

    I went to the students station and saw that they had a stoppered, N2 purged 25 mL round bottom that was filled with sieves.

    I don’t know about the vermiculite story but my organic chemistry lab partner tried to run sieves through a sep funnel…

  17. Andrew Dalke says:

    “Real visible fluorine” http://www.theodoregray.com/PeriodicTable/Elements/009/index.s7.html
    The picture of it looks brown.

  18. Marc says:

    That`s the way that academic labs are. Most of it sounds trivial for anyone who has worked in a lab for any period of time. but take a look at it from the newbie`s point of view. You have a box labeled ‘Bromine’ with a bunch of chemical looking stuff in it. He is not going to stick his arm elbow-deep in it to see if there is a bottle at the bottom.
    I once saw someone dump conc. chlorosulfonic acid in ‘chloronated waste’. It makes sense, right ? I was standing close enough to have a few holes burnt in my shirt (note to self: wear natural fibers in the lab) a 3rd person got a drop on her arm. (2nd note, don`t all stand together when someone is handling that stuff so at least one of you will avoid getting hit by shrapnel… or at least stand behind someone large and meaty)
    The problem is that common sense isn`t so common in the lab. it has to be leared. and taught.

  19. Kim says:

    You think this only happens in labs? I had a Taiwanese friend who was given written instructions on how to care for a hamster while her roommate was out of town. Two weeks later, roommate came home to see skinny hamster – turns out the friend had been trying to feed him vermiculite as she “couldn’t find” his box of hamster chow in the cupboard! Duh, it was the big box with the picture of the hamster on it.
    And don’t even get me started on the sloppy undergrads who were trying to do some after-hours iodination and ended up in the hospital due to their mysterious medical problems. The university lab had to be decontaminated due to the amount of I-125 that ended up absorbed into the tile and cement underfloor.

  20. shmoo says:

    I have seen multiple students try to stir reactions on a magnetic stirplate without a stirbar.

  21. Renee says:

    In grad school, a POSTDOC in the chemistry building had some carbon disulfide (strong sulfur odor) that he no longer wanted. He theorized that it should have a solubility in water comparable to that of carbon dioxide. So, the postdoc poured the carbon disulfide down the sink, with some cold water running.
    Three buildings had to be evacuated, since the fumes from the CS2 traveled through the plumbing into neighboring buildings. It took several hours to clear the odor from the buildings. And yet, the postdoc’s professor covered for him.
    But what about me when I was a summer student – a chemist supervising me said to put a warm Erlenmeyer flask in the icebox. So, I went to the plastic box in the lab that held crushed ice, and put the flask in there. An hour later, he asked me why I’d done that. Turns out, he wanted me to put the flask in the refrigerator.
    Another story – in grad school I was once asked by a postdoc (Ph.D. organic chem, Ivy League school) how to dissolve sodium sulfate in water. What he’d done was take a 2-inch square chunk of it, dumped it in water in a beaker with a mag. stirrer, yet he couldn’t understand why it wouldn’t dissolve. I had to tell him to crush the salt into smaller pieces first. Voila!

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