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I think every blackboard organic chemistry class should be required to be taught with multiple repeated asides about the dangers of organometallic reagents. A

• ashtonkem 5y ago
  Even as a lay person I know that most fluorine molecules are not to be messed with.
  • dheera 5y ago
    Uh, except the stuff you shove on your toothbrush? The high-dimensional surface of "threat to life" vs. molecule structure is super, super, non-convex. Like H2O -> yay, H2O2 -> die, H2 + O2 -> fire Like methanol -> die, ethanol -> fun, propanol -> die, butanol -> die, heptanol -> die, octanol -> die
    • rakejake 5y ago
      My high-school chemistry teacher had this joke: "If you drink Ethanol you dance around people, if you drink Methanol, people end up dancing around you". For context, certain communities in India have people dancing around the funeral procession.
      • Cerium 5y ago
        The rhyme I was taught: Little Johnny was a chemist, little Johnny is no more. What he thought was H2O was H2SO4.
    • ashtonkem 5y ago
      And that’s why I said “most”.
    • masklinn 5y ago
      > Uh, except the stuff you shove on your toothbrush? Fluoride is an exception, only in small quantities, and only topically (lots of salts are toxic, and so are concentrated solutions). By and large fluorine chemistry is a giant pile of nope, so staying away from it is an excellent rule and quite far from a “super, super, non-convex”.
      • gpcr1949 5y ago
        Many marketed small molecules have fluorine in them, organofluorine compounds are sometimes in fact preferred because they are metabolically more stable than the non fluorinated compound. example of some drugs that have more than 1 billion $ sales/year net that contain fluorine: bictegravir,enzalutamide,elexacaftor,paliperidone,sitagliptin,olaparib,teriflunomide.
    • FreeFull 5y ago
      1-Propanol acts like ethanol, but stronger, so you'll be fine if you don't ingest too much. 2-Propanol on the other hand (isopropyl alcohol) gets metabolised into acetone, which isn't great. And the only difference between the two is the way the atoms are arranged!
      • amelius 5y ago
        Acetone is in the breath of people who are on a keto diet.
        • netizen-936824 5y ago
          That's likely a far lower concentration. The dose makes the poison.
      • BeFlatXIII 5y ago
        How different is the LD-50 between EtOH and 1-propanol?
    • 01100011 5y ago
      Some amyl alcohol isomers have been investigated as ethanol replacements because of the similar effects, albeit at lower doses, and an absence of a hangover due to less toxic metabolites. They're also commonly found in fermented beverages. Dose makes the poison and all that.
• addaon 5y ago
  Yes. I've often heard (although it appears to be an open question[1]) that chemists have a significantly shorter life span than the general population. [1] https://pubs.acs.org/doi/10.1021/cen-v049n010.p005 https://pubs.acs.org/doi/10.1021/cen-v049n010.p005
• epolanski 5y ago
  I'm a chemist done research. Information is known, but procedures are more often than not, not respected. In perovskite research there is a lot of toxic and dangerous materials, e.g., people would still ignore it. It's hard to explain but my experience in labs is easily explainable with covid. All started cautious but in the end most aren't that thorough and safe.
• Natsu 5y ago
  Yeah, most of the time I've read about such compounds it was via blogs, like this one on dimethylcadmium: https://www.science.org/content/blog-post/things-i-won-t-work-dimethylcadmium https://www.science.org/content/blog-post/things-i-won-t-wor... "I'm saddened to report that the chemical literature contains descriptions of dimethylcadmium's smell."
  • stevespang 5y ago
  • Natsu 5y ago
    @stevespang - All your comments seem to be [dead] and I don't see an obvious reason why you would be shadowbanned after looking at the last several. You might want to talk to HN.
• gpcr1949 5y ago
  Agreed, though of course not every organometallic reagent is alike. It's quite alright to let students try to do a Grignard reaction (the generation of the Grignard reagent being famously finnicky in the hands of beginners and experienced chemists alike) once they have safety training behind them, it's quite another thing to let them work with even more flammable, explosive or toxic compounds. Some other more benign organometallic compounds are porphyrin and phtalocyanine dyes and various nicely colorful coordination complexes. One other sad incident with organometallic reagents was the death of Sheri Sangji[0], she was scaling up a reaction involving tert-butyl lithium, which resulted in a deadly fire. It was thought the accident was a result of a series of safety failures (bad safety education, bad ppe, weekend work) and the university and supervisor were (imo, correctly) held culpable for creating the conditions in which such a horrible accident was possible. This one is also quite scary because many organic chemists will routinely use n-Bu-Li and occassionaly tBu-Li, the deadly and more pyrophoric agent involved in this accident as well. [0]https://en.wikipedia.org/wiki/Sheri_Sangji_case https://en.wikipedia.org/wiki/Sheri_Sangji_case
• bsder 5y ago
  > It's a major oversight for student education -- to be taught the dangers of the subject you're about to be exposed to in real life. Organic chemistry used to teach people to pipette with their mouth because the alternative was too expensive. Okay. These are the level of cowboys in the field. The Austin Fire Department had to threaten to let the UT Chem Building burn to get them to straighten up. Even Derek Lowe (https://www.science.org/blogs/pipeline https://www.science.org/blogs/pipeline) talks about teaching a lab where the ether solvent was giving him migraines for an entire semester. And, of course, we have Mex Gergel's Superfund-level toxic dumpsites described in "Excuse Me Sir, Would You Like to Buy a Kilo of Isopropyl Bromide?" Organic chemistry seems to attract these kinds of people for some reason.
  • fuzzfactor 5y ago
    I worked for one of the companies mentioned by Gergel which ended up as a Superfund site after it had closed. We distributed some of his creations and he some of ours. There is always some risk in handling chemicals, even more so making new ones from scratch. This does not so much attract those driven by risky behavior, rather those who can tolerate the risk remaining after effective mitigation. With toxic chemicals it's good to have a safety culture. Historically, with more common toxins like benzene, it was often handled without gloves up to at least the mid 1970's when the effects of long-term exposure became more widely recgonized. Regardless from the very beginning benzene had always been handled with no smoking, lighters, or open flames, and with a respirator when the operator deemed necessary. Most days gloves were just plain never worn except for well-recognized major immediate hazards like pure sulfuric acid, and disposable gloves had never become a consideration since they were plain latex which is not very chemically resistant, too thin & skin-tight, basically as the name implies "surgical" gloves for physicians & nurses to maintain a more sterile enviroment and protect the patients from contaminants on the workers' hands, not as much to protect the workers themselves. Industrial nitrile gloves were already up to today's standards but these were orders of magnitude more costly than medical disposables, much thicker, not tight at all, can last for years and be easily slipped on & off quickly for instance every time an entry needs to be made in a lab notebook without taking the chance of touching the notebook with any contaminated gloved hands ever. Workers were expected to take very good care of their prized modern nitrile gloves so they would be ready every time when needed, unfortunately this was so seldom that often they couldn't find their personal gloves quick enough, and poured the sulfuric without using them anyway. Or perhaps even more risky, using someone else's gloves, other than the specific pair they had been issued and expected to provide dedicated care & maintenance of along with their personal respirator. You didn't need these things most of the time, but when you did nothing else would do. And you never knew how contaminated someone else's PPE might have been. By the 1980's litigation was alarmingly through the roof everywhere and toxic chemicals are a very difficult-to-defend target. Mandates came down for workers to wear nitrile gloves for every single chemical with any kind of hazard at all. Materials like acetone, dilute acids, brine solutions etc. that had been handled safely without gloves for generations now triggered the requirement. Some operators who seldom wore gloves now needed to wear them most of the time from that point forward. If you wore them all the time it was felt you were protected all the time. Culture changed. It became a no-brainer. Cue the arrival of disposable nitrile gloves, the full-strength originals were just too expensive for everyday use. The inflation from 1971 to 1976 had made sure of that. Culture changed further. Eventually the appearence of a gloved hand holding a test tube is no longer a red flag that it likely contains one of the very few (in most labs) highly toxics that truly require the most extreme care. Today I've got workers going through pallets of disposable gloves for every pair of traditional personal nitriles. Other companies haven't issued personal gloves of any kind for decades, nitrile or not. And I never dreamed the doorknobs and keyboards on the office machines would become so suspect for toxins compared to how it was before gloves became ubiquitous. Lab notebooks today might be safer to handle only with gloves and not enter non-chemical offices. Remember PPE stands for "Personal Protective Equipment" and its not very personal if it's a throwaway and can be treated like an afterthought rather than a personal possession. This methylmercury fatality could likely have been prevented if the disposable nitriles had never arose. No doubt the victim would have been wearing the thick non-tight original gloves instead, which might have provided protection anyway even though the nitrile composition is just not completely impermeable to this particular toxin. Would have to safely discard the contaminated non-disposable gloves also since this is a lingering hazard rather than something like an aggressive acid which can be washed off the gloves afterward.