4/07/2007

solid-state synthesis: sans solvent?

Stuart at The Sceptical Chymist recently did a quick interview with Mike Zaworotko, so I'll continue what he started and point you in the direction of a recent paper in Crystal Growth & Design.[1]

The idea behind it is C3S3, which is a much faster way of saying co-crystal controlled solid state synthesis. Naphthalenetetracarboxylic dianhydride (NTCDA) and an amine were ground together with maybe a drop or two of solvent thrown in. Heating gave a co-crystal of the two. The co-crystal was then heated like crazy to give the corresponding diimide.



I'm guessing that the product was not so soluble, which might explain why they recrystallized using DMSO or DMF. I'm pretty sure the corresponding perylene diimide would be brickdust. Still, greasy amines (with looong alkyl attachments) would probably be too volatile for this.

In any case, it's an interesting little paper that caught my eye, and I needed to post something, so here it is. You might expect to see more crystal engineering-related lit on CBC in the next month or so, by the way, since I've been staring down a few of those papers lately.

[1] It has to be pure coincidence that everyone covered in Sceptical Chymist's Reactions so far is doing something I find interesting. I will attribute this to Stuart's fantastic taste in subjects rather than mind-reading.

15 comments:

Liquidcarbon said...

The dianhydride looks a bit like a kitten, if you stare long enough. (3:23 AM)

Ψ*Ψ said...

Liquidcarbon: when you start hallucinating and there are no drugs involved, it is generally time to go to sleep.

Excimer said...

"heated like crazy"

when most of your reactions are refluxed at 250 °C for a few days, your standards for "holy crap that's hot" go way, way up. 130 °C is for pussies. Nevertheless, any solvent-free reaction is automatically delegated to the "oooo neat" category.

Ψ*Ψ said...

Actually, the highest temperature I use in the lab is about 140 C for the molten-solvent reaction I posted a while back...unless you count fires?

Uncle Al said...

What a boring amine.

Co(en)3 + HCHO + MeNO2 gives Co(dinosar)(3+) [One wonders about inexpensive commercial disinfectant trimethylolnitromethane, 2-(hydroxymethyl)-2-nitro-1,3-propanediol)

https://www.chem.ubc.ca/faculty/wassell/CHEM310/Experiment_12/Reference1/E12Ref1.htm

(Optically resolve) Reduce to the diamsar diamine, make (chiral) redox nylon for the E*L**E*C*T*R*I*C car or hydrogen peroxide for wood pulp bleaching without TCDD formation. What is wrong with this picture (aside from Enviro-whining)? Would using nitrobenzaldehyde for HCHO fix it, including angular systems to reduce polymer crystallinity?

Ψ*Ψ said...

Meh. In this case, "boring" worked.

Liquidcarbon said...

Monday, 12:25 PM.
the dianhydride still looks like a kitten.

Matt Jenks said...

I actually used a similar reaction scheme back at my old job while trying to pop an imide piece that was associated with a certain Kinase Inhibitor. I'd never done anything so hot before, so I was (and still am) fascinated by the notion of taking something up to 250 degrees and stirring it for 18 h.

One thing, though, was I used TEA-HCl as a salt for the base, and I thought that was odd but didn't think about why I was using that (took the prep from a paper...original science and my old company don't exactly go hand-in-hand) but after reading your post it became obviously, painfully clear.

ElwoodCity said...

I did a solid state intramolecular diels-alder once. Mix the acid cholride with 3 eq AlCl3, and heat the powder at 210 until it stops smoking. Well, to tell you the truth, it turned black whenever I did it, but it worked great for our post-doc. But that's the same guy who runs enzymatic reactions at 37 degrees by keeping the flask in his pocket.

Alexander said...

I refluxed a reaction in nitrobenzene for 6 days.

You can make 4-methylindole by heating neat N-formyl-2,3-dimethylaniline with t-BuOK at 250 or 300 C...

Stu said...

Thanks for the shout-out. Wish I could claim to have my finger on the pulse of all that is cool in chemistry, but so far the selection criteria has mostly been based on who said yes... I hope they continue to be interesting...

Ψ*Ψ said...

I only hope that they also say "yes" when asked whether they are accepting grad students.

mevans said...

Howdy! Indeed we DO have a class together! A class I hate, unfortunately...Atwood somehow always picks questions for the exam that I don't study/care about. Go figure.

See you around!

PS feel free to link to my blog...I'm brand new to Blogger so I don't really know how things work...so yeah.

Ψ*Ψ said...

That exam was not my friend either. Ick!

Elinker said...

You can bet your bottom dollar that the molecule is pretty much insoluble, with those nitro groups, those diimide bits, the rigid structure and aromaticity. There's no thing soluble in that molecule at all.

Might as well go and scoop some soil up and use that.