[Humr]

Hi. I would like to ask if someone has any experience with phenyl oxalate esters used for glow sticks. I made these 3 esters. I have problem with determinating quality. I have played the most with ester 3. from my experience it is very sensitive. When i tried to dry ethyl acetate solution of this coumpound with MgSO4 it decomposed. I dont know how much, but clear solution turned yellow quite fast. It also decomposed on micro filter when preparing sample for LC/MS. I saw only dinitrophenol in mass spectrum. Also only vaniline in case of ester 2. When i disolved it in EtOAc and dropped a few miligrams od sodium acetate, it turned yellow also.

My question is if its normal for these esters or i just prepared some garbage. I can find very little informations about properties of these esters in literature.

When i tried glow stick reaction, I did it with ester 3. It was glowing very bright, but only in manner of seconds. I used ester 3, 30% H2O2, ethyl acetate, Rhodamine G6. To be honest, I did not measure exact molar ratios. I guess that would be good start and also make weaker solution of hydrogen peroxide?

I prepared all esters like this:

[rolnor]

Ester 3 is very reactive with the strongly electron-withdrawing 2,4-nitro groups, its likely that you even never did get this ester, the phenol startingmaterial is very unreactive. For the others I suggest chromatography and carbon-NMR, also mass-spectrometry.
Do you monitor the esterification reactions by TLC?
You need to have a reference how to run your glow-stick reactions and use optimal conditions.

[wildfyr]

I suspect these all vary in water sensitivity from "pretty water sensitive" to "decompose immediately in ambient air even in a desert"

[rolnor]

Yes, compound 3 is like acetyl chloride (!)

[wildfyr]

You know, I bet you could run this reaction in an NMR tube. You should be able to see the proton especially at the 5 position shift during the reaction.

Just seal it up real nicely, and definitely use some excess of oxalyl chloride and TEA.

Also... did you dry your TEA? It can absorb some water.

[Humr]

I dryed TEA with KOH. I am sure i prepared esters 2 and 3. Both can make it glow (1 did not). Problem is that it glows for 30 seconds at best. For preparation of vaniline ester i followed this article https://doi.org/10.1021/ed100597n. At least i tryed. They claim vaniline solution turns yellow when TEA is added. It never happened to me. Also they used EtOAc for extraction in pritty small portions. These esters are nigtmare to disolve. Especially vaniline one. Final product in article was light yellow solid. My product is white. I tested our vaniline on LC/MS - its ok. TEA is used in our lab daily, so it should be OK as well. I tryed 2 bottles of oxalyl chloride and reaction behaved same.

I tryed 2 dyes. Rhodamine B and Rhodamine 6G. B glow was very weak and short. 6G brightnes was ok but short. I dont have any other dyes to test.