Sciencemadness Discussion Board - Original Jack Roberts compounds

Original Jack Roberts compounds

numos - 8-3-2020 at 21:40

Came across a set of compounds which were made in the lab of Jack Roberts. I've taken pictures of some of the interesting ones - really classic samples in their original containers and labels. The cyclobutenes especially, are notable as they were used in the development of NMR prediction and understanding spin systems.

There are many more, but some are decomposed and some don't have all that interesting structures. These are the highlights.

Dr.Bob - 9-3-2020 at 17:40

Neat find. I always want to save everything like that until I realize I have nowhere to put it all. I have some books from Gertrude Elion's collection in my books. Sadly, unlike most people, she did not write her name in every book, so they are not very collectable. But still neat to have a little piece of history. PS, If anyone wants some similar samples, we have about 20 bins of poorly labelled or unknown vials like that from chemists who retired...

Amos - 10-3-2020 at 06:37

Did you maybe mean John D. Roberts?

Heptylene - 10-3-2020 at 13:03

Incredibly cool find! Do you know how old they are approximately?

And one of them is apparently labelled with carbon-14! Do you have a geiger counter to check it?

numos - 10-3-2020 at 14:29

Quote: Originally posted by Heptylene

Incredibly cool find! Do you know how old they are approximately?

And one of them is apparently labelled with carbon-14! Do you have a geiger counter to check it?

Jack Roberts died just a few years ago so these compounds can't be more than 60-70 years old. In fact I talked to one of his students who worked on the cyclobutenes as a grad student. He's 90 ish now so those compounds are from ~1950.

Don't have a Geiger counter, but I can ask around here!

Also Amos, Jack was a nickname he preferred to go by, but you are right, his legal name was John.

phlogiston - 10-3-2020 at 14:50

The label on the ampoule with the 14C-labeled compound is marked 4/29/53, which I presume is a date.

BTW, you're unlikely to pick up much if anything with most common Geiger counters. The beta-radiation from 14C is very weak. The glass will block much of it, and even without glass (but I don't recommend opening that ampoule!), you'll need a probe that is suitable for picking up low-energy beta's.

[Edited on 10-3-2020 by phlogiston]

Heptylene - 10-3-2020 at 17:02

Quote: Originally posted by phlogiston

The label on the ampoule with the 14C-labeled compound is marked 4/29/53, which I presume is a date.

BTW, you're unlikely to pick up much if anything with most common Geiger counters. The beta-radiation from 14C is very weak. The glass will block much of it, and even without glass (but I don't recommend opening that ampoule!), you'll need a probe that is suitable for picking up low-energy beta's.

[Edited on 10-3-2020 by phlogiston]

Fair point, but there will be some x-rays from the beta particles stopping in the glass. I think the max. 156 keV betas of 14-C might produce a response on a typical tube. It's worth a shot.

numos - 11-3-2020 at 18:59

Quote: Originally posted by Heptylene

Quote: Originally posted by phlogiston

Fair point, but there will be some x-rays from the beta particles stopping in the glass. I think the max. 156 keV betas of 14-C might produce a response on a typical tube. It's worth a shot.

Went ahead and did this. I don't have a Geiger counter but my geologist professor friend had a good one. It was picking up low doses (I think ~0.01 mR/hr but I may be reading this wrong) through the glass. But only through the tube opening, meaning no x-rays/gamma rays. Just a few high energy betas that made it through the glass. It was definitely a spike from background.

Great idea and neat result - thanks!