Friday, April 28, 2017

Catalytic Hydrogenation - A Farewell to Alcohol(s)

We have a project in my group on bitopic ligands targeting the adrenergic receptors. We recently published a perspective paper on the topic that you can check out here. Anyway, today we had a project meeting regarding the synthesis of bitopic salbutamol analogues.
To this end, one of the guys wanted to synthesise an epoxide as outlined above. However, to his (and everyone else surprise) even under mild conditions he managed to loose both of his benzylic alcohols in the process. The crude product is of excellent purity and he isolated the over-reduced phenol in >90% yield.

This is a common problem but it really is trial and error. I would say that the case above is the most extreme example I have seen considering that it was run at atmospheric pressure and room temperature. It brought memories back from when I was a PhD student. The very last reaction I did in the lab was an attempt to reduce an alkene, however, as you can probably guess what I got out as the major product was the deoxygentaed molecule. However, this reaction was somewhat more messy than that above and the desired molecule may have been hiding in the mixture as well. D!

Wednesday, March 01, 2017


I guess it is old news but it only caught my eye today at the BBC website. Apparently Nature did a survey last summer (2016) were scientist were asked if they had "failed to reproduce another scientist's experiments"? What really surprised me was that only 70% on average said yes to that question. Obviously, scientists from all disciplines participated in the survey and chemistry did better in reproducibility than biology and medicine (when judged by themselves) but it looks pretty bleak overall. In synthetic organic chemistry, I would estimate that >95% of chemists have been unable to reproduce a published synthesis (as in get any of the desired molecule and not necessarily just the same high yield). Personally, I have had methods across the impact factor landscape fail in my hands, from Synlett to Nature Methods. On more than one occasion everything has just decomposed and gone black. Unless it is published in Organic Syntheses it's a bit of a lottery. Anyway, both articles are quite interesting and worth reading (although they are somewhat depressing). D! 

Monday, February 20, 2017

Dry Column Vacuum Chromatography (DCVC) - The Movie!

I have on several occasions been asked to make a DCVC video tutorial and quite liked the idea of doing so. Thus, I have started my acting career as you can see in the video below. I think the video will be a useful guide for first time DCVCers. For more info you should consult this and this blog post on DCVC. Many thanks to the University of Copenhagen's Communication Department, in particular Jacob Lejbach Sørensen, for investing some time in making this possible. D!