Sciencemadness Discussion Board

DBDMH / 1,3-Dibromo-5,5-dimethylhydantoin - OTC USA?

FireLion3 - 20-7-2014 at 21:29

I recently learned about this as an exciting alternative to NBS. I remember glimpsing a similar compound in stores, but it was 1-Bromo-3-chloro-5,5-dimethylhydantoin (BCDMH). The chlorine content makes this no good for me, and I found many other chemists here felt the same way.

DBDMH is available from some online suppliers, but at nearly 10x the cost of BCDMH. Searching for DBDMH tablets online under the various trade names did not turn up much, except I was able to find numerous suppliers in China... but right now I'm not willing to purchase 1 metric ton. How come there are so few US suppliers with these tablets? Why the Bromo-Chloro mix?


[Edited on 21-7-2014 by FireLion3]

UnintentionalChaos - 20-7-2014 at 21:48

You can manufacture your own tribromoisocyanuric acid which has similar properties by adding bromine to a solution of trisodium isocyanurate (isocyanuric acid is available as pool chlorine stabilizer). The TBCA seperates out as a solid.

A word of warning, however, the cyanuric acid typically available for purchase as a pool chlorine stabilizer is just waste product from manufacture of trichloroisocyanuric acid or sodium dichloroisocyanurate. It is typically partially chlorinated. Add HCl to it somewhere with good ventilation and let the Cl2 blow away. The acid may be recrystallized from large volumes of boiling water (and forms a dihydrate that readily dehydrates with heating).

FireLion3 - 20-7-2014 at 22:00

That's interesting, thank you, though, if I could get the bromine then I could skip the need for this reagent all together :D.

I looked into trichloroisocyanuric acid, the biggest reason I am turned off from it is because both it and its subsequent dehalogenated form are not soluble in water. With DBDMH/BCDMH, the dehalogenated form soluble in water, allowing for easy removal. If I were to use Tribromoisocyanuric Acid as a brominating agent, I would be stuck with the task of separating the organics from the byproduct - easily done with a distillation, but I'll pass.

UnintentionalChaos - 21-7-2014 at 00:01

Quote: Originally posted by FireLion3  
That's interesting, thank you, though, if I could get the bromine then I could skip the need for this reagent all together :D.

I looked into trichloroisocyanuric acid, the biggest reason I am turned off from it is because both it and its subsequent dehalogenated form are not soluble in water. With DBDMH/BCDMH, the dehalogenated form soluble in water, allowing for easy removal. If I were to use Tribromoisocyanuric Acid as a brominating agent, I would be stuck with the task of separating the organics from the byproduct - easily done with a distillation, but I'll pass.


NBS and elemental bromine fill different roles, you know. If you want double addition across an unsaturation, you want the element. N-bromoimides are useful for halohydrin synthesis and free radical bromination (such as an allylic position where Br2 would add across the bond instead.

TCCA has pretty awful solubility in everything barring conc. sulfuric acid and polar aprotics like DMSO. Most of the byproduct could be filtered off from reactions.

FireLion3 - 21-7-2014 at 02:07

Good point.

I actually managed to find some DBDMH online. Sold under chlorine free "Brilliance Spa Sanitizer"

http://cdn1.bigcommerce.com/server700/jnapaiw/products/446/i...

Which according to the label is 99.4% DBDMH and "111% Available Bromine".

Only problem is I can only find this in 1.5 lb quantities, which isn't a problem seeing as it is only $13... which is awesome!