Back at work!


We are slowly returning to our „new normal“ at BOKU, Vienna. Generally, we work in 2 shifts trying to avoid as much of a contact as possible. We wear face-nose mask protection at all times in addition to regular pre-COVID times. One of the new stress factors is to finish all that you plan within 6 hours of your shift. Briefly, I would like to share a story that happened this week. Personally, I will remember this for a while.

Shift is yours - use it your very best

Within this time span of 6 hours , I planned to perform a more-or-less quick triflation reaction, that would be followed by azidation reaction taking place overnight to satisfy the requirement of an extended reaction time. At the beginning of my shift I felt like I am going to make this without any problems and so it went like as well. I got the spot of my formed triflate, let it evaporate, HV-line for an hour to get nice yellowish crusty solid material in a quantitative yield. As I calculated the excessive amount of sodium azide (NaN3) needed, clock started ticking… Just 20 minutes before shift ends.

Know your stuff

I recalled the very position of my NaN3, so I grabbed it, balanced it and swifted it in to my sugar in DMF reaction mixture. But there was certain yellowish color change that made me wonder immediately. So I looked at the bottle from which I added my reagent. Oh my … it is sodium phosphate … white powder, just as sodium azide packed in exact-looking grey container. And that was just 10 minutes before ending the shift. I got a bit anxious, I have to admit. I did make a mistake and that stressed me out, but I also realized, that sodium phosphate should far from soluble in DMF, even at 75°C.


Well, I rushed through the hallway to the storage room to get the very NaN3, balanced that in – hoping it would fix the issue. I made it just 5 minutes after 1PM, but it was done. I had to leave the lab, not knowing if the presence of (basice) phosphate would not interfere with the protecting groups of my sugar compound. I hoped not. I was cheering for an azide to do it’s job quicker if there is to be any competing between azide and phosphate.

That day I left the lab in a question. Partially mad at myself for making a 1st grader mistake, but I was still able to justify why in fact should the reaction turn out well. I kept thinking about it and was impatient to see the TLC plate the following morning.

Hurray! It is there. Spot to spot, full conversion with tiny bits of some by-product. The heavy burden was gone, product to be isolated and purified and my day could not start any better.

Such days await organic chemists as well. Take-away message from me and also for me is simple – read the labels carefully!

Check my instagram for photos! https://www.instagram.com/p/CBEImw7jVTN/

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