Sciencemadness Discussion Board

tcca, bromine and ncl3

Gui316 - 13-9-2011 at 05:36

i was just wondering if is there anything like tcca, but with bromine , flourine or iodine in place of the chlorine. i would like to know what happens when tcca is reacted with aqueous ammonia. would it yield trichloramine? what happens if is calcium hypochlorite is reacted with ammonia?

barley81 - 13-9-2011 at 12:54

http://woelen.homescience.net/science/chem/exps/raw_material...

That website answers your question. According to wikipedia, tribromoisocyanuric acid exists. Go visit the page for more. I think when calcium hypochlorite is reacted with ammonia, nitrogen will be the main product, but also chloramine (also dichloramine and nitrogen trichloride) and hydrazine will form.

The WiZard is In - 13-9-2011 at 16:01

Quote: Originally posted by Gui316  
i was just wondering if is there anything like tcca, but with bromine , flourine or iodine in place of the chlorine. i would like to know what happens when tcca is reacted with aqueous ammonia. would it yield trichloramine? what happens if is calcium hypochlorite is reacted with ammonia?



Nonconfrontational facts about household chemicals Mentioned here earlier was
"the vast amount of chlorine given off by reaction of Clorox (about a 51% solution of
sodium hypochlorite) with products like Vanish, detergents, and ammonia" (C&EN,
Sept. 19, 1988, page 56). These words being slightly off the mark, an anonymous
correspondent wishes "to point out a few facts in a nonconfrontational manner."

He or she writes that a pH dependent equilibrium exists among hypochlorite,
hypochlorous acid, and chlorine. "Above pH 7.5, hypochlorite ion predominates. Some-
where around pH 5 it becomes possible for free chlorine to exist in solution. The rub is
that chlorine is much less soluble than either HOCI or OCI, and at about pH 2 or 3 it
comes boiling out. This is why you don't mix chlorine bleach with acids. A
garden-variety toilet bowl cleaner is usually a moderately strong acid such as
phosphoric acid or sodium bisulfate, which easily delivers a pH around 2. It's amazing
how much chlorine you can get out of a pint of bleach. That's why products like Clorox
bleach and Vanish toilet bowl cleaner carry ... warning notices on their labels. Isn't it
amazing how few people bother to read?"

Ammonia is a different case, the correspondent goes on. "Mix an ammonia solution
with hypochlorite and you get chloramines-NH2Cl, NHCl2, and NCl3. The chloramines
are alkaline but less soluble than ammonia, so they bubble out. They are also
poisonous. That's what happens when you mix hypochlorite bleach with household
ammonia.

"So what happens when you mix bleach with detergents? Clean clothes."

Chemical and Engineering News Janurary 2, 1989

-------
Extracted from —

MMWR September 13, 1991 / 40(36);619-621,627-629

Epidemiologic Notes and Reports Chlorine Gas Toxicity from Mixture of Bleach
with Other Cleaning Products – California

When bleach is mixed with ammonia-containing compounds, monochloramine
(NH2Cl) (Figure 1c) and dichloramine (NHCl2) (Figure 1d) are formed, which
may produce tearing, respiratory tract irritation, and nausea. These compounds
decompose in water to hypochlorous acid and free ammonia gas (6-8); the
former combines with moisture forming hydrochloric acid and toxic nascent
oxygen (8); the latter is a respiratory and mucous membrane irritant and can
cause pulmonary edema and pneumonia (6,7).

6. Faigel HC. Hazards to health: mixtures of household cleaning agents. N Engl J
Med 1964;271:618.
7. Gosselin RE. Clinical toxicology of commercial products. 5th ed. Baltimore:
Williams and Wilkins, 1984:111-204.
8. Gapany-Gapanavicius M, Molho M, Tirosh M. Chloramine-induced
pneumonitis from mixing household cleaning agents. Br Med J 1982;285:1086.

DJF90 - 14-9-2011 at 06:22

Triiodoisocyanuric acid also exists, and can be made via finkelstein reaction on TCCA.

ScienceSquirrel - 14-9-2011 at 07:10

I suspect that the trifluorocompound can also be made from TCCA and a suiltable fluoride by halogen exchange.
I suspect that it is rather inert.

solo - 2-1-2013 at 09:38

Quote: Originally posted by DJF90  
Triiodoisocyanuric acid also exists, and can be made via finkelstein reaction on TCCA.


Would this also be true for preparing TBCA (tribromoisocyanuric acid), via the finklestein reaction using KBr ....what solvent?.......acetone?......solo

Valentine - 2-1-2013 at 10:17

I have seen an empty can of trifluoroisocyanuric acid in a lab a few weeks ago. Its owner said this compound is very toxic and extremely corrosive.

[Edited on 2-1-2013 by Valentine]

TBCA preparation

solo - 3-1-2013 at 20:13

Bromine Derivitives of Cyanuric Acid
John A. Wojtowicz
The Chemistry and Treatment of Swimming Pool and Spa Water
2004,Volume 5, Number 2, pages 16–19


Abstract
Various bromine derivatives of cyanuric acid have been prepared and characterized. These
include: partially and fully brominated derivatives of di- and trichloroisocyanuric acids, and
sodium dichloroisocyanurate. In addition, partially brominated derivatives of the double salts of
trichloroisocyanuric acid and potassium dichloroisocyanurate are possible. The bromine
derivatives have lower solubilities than the chlorinated analogs. None of these compounds have
been commercially developed.

..........the pdf can be donwnloaded at the vespiary.org in the reference area under articles of interest......solo

DJF90 - 3-1-2013 at 20:24

@Valentine: Are you sure the compound in question was trifluoroisocyanuric acid, and not cyanuric fluoride, a (relatively) common peptide coupling agent?

Valentine - 4-1-2013 at 02:32

I'm not 100% sure, but I think it was trifluoroisocyanuric acid. I will check it again on monday.

Vargouille - 4-1-2013 at 05:14

The reference that Solo quotes (link here for ease) is not particularly useful for the preparation of tribromoisocyanuric acid, as it suggests a reaction between trisilver cyanurate and bromine.

If it is interesting, I recently found a Brazilian article that mentions the creation of triiodoisocyanuric acid by way of reaction between trichloroisocyanuric acid and iodine, with periodic distilling off of iodine monochloride.

Attachment: a02v19n7.pdf (161kB)
This file has been downloaded 492 times

solo - 4-1-2013 at 09:10

"TBCA is a stable solid that can be easily synthesized
from isocyanuric acid and NaBr in the presence of oxone.3"

.....source,

TBCA mediated microwave-assisted Hofmann rearrangement
Leandro S.M. Mirandaa, Thayane Rabello da Silvaa
Tetrahedron Letters
Volume 52, Issue 14, 6 April 2011, Pages 1639–1640
http://dx.doi.org/10.1016/j.tetlet.2011.01.126

Abstract
A protocol for the microwave-assisted Hofmann rearrangement mediated by TBCA/KOH/MeOH was developed. Under these conditions high yields and short reaction times were observed for aromatic benzamides.

Attachment: TBCA mediated microwave-assisted Hofmann rearrangement.pdf (174kB)
This file has been downloaded 1310 times

AndersHoveland - 4-1-2013 at 11:32

Quote: Originally posted by barley81  
I think when calcium hypochlorite is reacted with ammonia, nitrogen will be the main product, but also chloramine (also dichloramine and nitrogen trichloride) and hydrazine will form.

I would be interested to see a quantitative investigation into exactly what the exact proportions are of the products that form from this reaction.

I am sure the reaction products are very dependant on reactant ratios, pH, reaction time, and other conditions. The oxidation of ammonia by chlorine is a much more complicated reaction than is commonly thought, and there are several equilibriums going on in the solution, as well as several different reaction pathways. Under favorable conditions, I think good yields of chloramine can be formed, not just in trace ammounts.

equal ratios of hypochlorite to ammonia, low concentrations or reactants, high pH, and short reaction time, favors the formation of chloramine. The chloramine bubbles out of the reaction as a gas. This might explain why it tends not to be further destructively oxidized, because it escapes from reaction as it is formed. Chloramine is less soluble under alkaline conditions, although alkaline conditions also promote its decomposition. Chloramine is also not stable above certain concentrations.

a large excess of ammonia tends to favor hydrazine, but there are several specific reaction conditions required to get even moderate yields, since hydrazine tends to be oxidized faster than it is formed. Often a gelatinizing agent is added to moderate the reaction.

the formation of nitrogen trichloride is favorable at a pH around 4, which can optimally be achieved by passing chlorine gas into a solution of ammonium sulfate. At lower pH, however, the NCl3 tends to hydrolyse into ammonium ions and hypochlorous acid. Solutions of NCl3 dissolved in carbon tetrachloride decompose to their elements when heated. (nitrogen trichloride is very hazardous to prepare, the oily droplets that form in the bottom of aqueous solutions can often result in violent explosions for seemingly no apparent reason, be sure to wear eye protection)

The oxidation of ammonia to nitrogen trichloride is not a simple oxidation, but apparently seems to involve some equilibrium:

Cl2 + H2O <==> HOCl + H[+]aq + Cl[-]

3 HOCl + NH3 <==> NCl3 + 3 H2O


I am not sure, but I think the formation of nitrogen is favored by alkaline conditions and longer reaction times.

[Edited on 5-1-2013 by AndersHoveland]

Riding the snake

Organikum - 4-1-2013 at 13:54

Quote: Originally posted by DJF90  
Triiodoisocyanuric acid also exists, and can be made via finkelstein reaction on TCCA.


References?

In special what solvent?

In acetone this would mean to to try to ride the snake and this snake well very well ride you instead, for TCCA in acetone is a good way to chloroacetone and tis reaction has to be with care, cooling and caution. Adding some iodine to the mix will make it of course much more entertaining, following the parole: If life is boring - risk it!

But well, give me a decent solvent not prone to halogenation for the finkelstein and i'll shut up....


/ORG

PS. Of course easily prepared triiodoisocyanuric acid would be the hit, I suspect that the Hofmann Solo mentioned (great reference btw! :D ) would be a charm with the iodo instead of bromo.
Dibromoisocyanuric acid is available at pool supplies and after my berst of knowledge will substitute for the tribromo in all reactions, just use 1/3 more and thats that.

[Edited on 4-1-2013 by Organikum]

AndersHoveland - 4-1-2013 at 23:03

Quote: Originally posted by Organikum  

But well, give me a decent solvent not prone to halogenation for the finkelstein and i'll shut up....

Probably stating the obvious here, but many number of common solvents can be used. Heptane, toluene, for example, which will not be halogenated, provided the solution is kept away from sunlight/fluorescent lighting and is not allowed to sit too long. The only reason that acetone reacts is that ketones are easily halogenated through their enol tautomer (at neutral pH the reaction takes several minutes).

Chloroform is another good solvent for dissolving the halogens.

Probably stating the obvious again, but TCCA is prepared by treating cyanuric acid with chlorine. It would probably make more sense to just react cyanuric acid with iodine, if that was the desired product.

This is from the Science Madness Library, "Cyanuric Acid and Cyanurates", G.B. Seifer:
Quote:

The reaction of C3N3Cl3 with HI gives an amorphous brown compound (CNI)x that decomposes on heating into paracyanogen (CN)x and I2. However, the cyanurate sturcture of (CNI)x is confirmed by the fact that when treated with hot water, it is hydrolyzed to give cyanuric acid. Therefore, the compound can be assigned the formula C3N3I3,
Quote: Originally posted by ScienceSquirrel  
I suspect that the trifluorocompound can also be made from TCCA and a suiltable fluoride by halogen exchange.

You might have a look at that paper also, it briefly mentions several methods to prepare cyanuric fluoride. One of them is by reacting C3N3Cl3 with SF4 or HF at -78 °C.

This may likely work with TCCA also.
Quote: Originally posted by ScienceSquirrel  

I suspect that it is rather inert.

I would not think so. While organic fluorides do indeed tend to be inert, that would not be the case here. Those carbonyl groups open up the molecule to reduction. To make a comparison to other related fluorine compounds, neither COF2 nor NF3 are inert. Fluorophosgene hydrolyses fairly rapidly in water, releasing toxic HF.

You might be wondering about SO2F2 while we are in this line of thinking, since you know how extremely inert SF6 is. SO2F2 (sulfuryl fluoride) is used as termite fumigant. It has a very low solubility in water (about 1g/L), but slowly reacts with it, with a hydrolysis half-life of 3 days at pH 7, but hydrolyses much faster under alkaline conditions, half-life 10 minutes at pH 8.3

[Edited on 5-1-2013 by AndersHoveland]