Friday, 28 January 2011

End of the Week...

        Everyone was in high spirits this morning. The sun was out, and more importantly we had all been paid. My two overnight reactions had changed colour and a quick sniff test (don't kid yourselves, everyone does it) showed a distinct change in smell. Who needs NMR when more important things like sight and smell can be used far more quickly?!

         The next step was a quick TLC test. To the uninitiated among you, this shows whether a reaction has finished or not. Wikipedia is your friend if you want to know more. The first one was done. Excellent. The second one, despite a change from colourless to yellow and from fishy amine smell to something resembling tortilla chips, was completely unchanged.
         Following a short period of stamping round the lab swearing, I did what I normally do in this situation, add more reagents and heat the crap out of it. Three hours of refluxing later, absolutely nothing had changed. That reaction was written off at this point and swiftly went into the waste solvent bottle. Chemistry ceased at that point for the week. A load of testing and maintenance at the weekend meant I couldn't start anything new... a crying shame.

         During my customary 3pm coffee/bitching about life session I was collared by my supervisor to talk an undergraduate through my PhD project. I've been after a project student to do my dirty work (as well as teach valuable lab skills to, obviously) for a while now so this was my opportunity. I put on my best smile and explained a year’s worth of failure in the most interesting way I could. All my ideas were frantically written on a whiteboard and explained to a completely bewildered third year undergraduate who looked like a rabbit in the headlights. Eventually I let him leave only to be thanked later by my supervisor for being so enthusiastic. This has never happened before so I didn't really know how to react. Needless to say, massive brownie points were earned for that. Enough in fact to be collared with another undergraduate at 5pm just as I was putting on my coat to leave. An even quicker run-through of my project followed resulting in a slightly scared girl looking at me as if I was some kind of blithering idiot. Oh well, all in a days work for your friendly neighbourhood chemistry blogger.

        I’ll do my best to post something tomorrow but I'm at home for the weekend. Who knows what my parents have in store? I'm not sure I want to know to be honest. If I don't get round to anything tomorrow, I’ll be sure to post a new lab mishap on Sunday. It's just a case of picking a good one; the post should hopefully write itself!


  1. Stop smelling your reactions! Just stop it!!

  2. Oh the smell test is the best...I work with sulfur compounds and you can certainly tell when things work and things dont lol

  3. A quick waft can tell you a lot in o chem.

  4. how do you know your product didnt just have the same Rf as your starting material? Ninhydrin is sometimes a good way of sorting this out- often nitrogen containing compounds will go different colours on the TLC even if the Rf is identical (co spot). I'd get torn a new one if i chucked a reaction without doing a crude NMR to prove nothing had happened...

  5. ...though i did monitor my hoffman elimination by smell the other day. The smell of methyl iodide was the start smell, the sweet smell of a,b unsaturated ketone was the product. electrophilic cancer?

  6. My PI tends to smell lots of reagents around the lab, noting that using yeast for certain enatioselective reductions makes the lab smell like beer and bread... I've definitely almost passed out from inhalation as well, but scents definitely tell you a lot.