Sciencemadness Discussion Board

Thallium (III) Nitrate Supported on K10 = practical approach to larger scaled oxythallations

zephler1 - 15-1-2014 at 20:34

Thallium(III)Nitrate has a very attractive way of oxidizing organics. However, it's cost vs. amount of feedstock it will react with (due to it's high MW) is a bit prohibitive, and it's safety could also be argued to be just not worth it to risk; Thallium exposure to make a small amount of a material does seem like a good risk vs. reward ratio. The stuff reacts in 5 minutes, then you must filter, and then if you want to react more, it seems that by the lack of literature, that your now formed Thallium(I)Nitrate is not worth changing back into Thallium(III)Nitrate, you you have to add more. Yes I realize that is probably just me making up the add more part; this is mainly due to frustration with not being able to find ANY info on transforming the (I) Nitrate to the (III)Nitrate.

There are many online references on how to get from Tl (I)O3 to Tl(III)NO3, but how does one go from Tl(I)NO3 to TL(III)NO3? Could it be as simple as exposing the species to excess HNO3? I cannot find any references on regenerating the (III) from the (I).

So let's assume it is a straight forward addition of HNO3 to the spent Thallium (I) Ntirate, regenerates the Thallium III Nitrate.

You prepare the K10 clay supported TTN as described here:

Thallium in organic synthesis. 44. Oxidative rearrangements via oxythallation with thallium(III) nitrate supported on clay.
1976 JACS, page6750.

Pack a column. Run your feedstock through at slow flow rate. Once the TTN has changed to the Tl(1)NO3, wash with HNO3 to reactivate and repeat? Hrmmm seems a bit too easy.


[Edited on 16-1-2014 by zephler1]

Thallium (I) nitrate to Thallium (III) nitrate?

zephler1 - 16-1-2014 at 10:14

I can't post the reference right now, but a stated method of producing Thallium (III) chloride from Tl(I)NO3 is with Aqua Regia; could nitric acid alone do the oxidation?

blogfast25 - 16-1-2014 at 10:29

CRC Ed 86:

Tl<sup>+</sup> === > Tl<sup>3+</sup> + 2 e ... Eox = - 1.252 V

NO<sub>3</sub><sup>-</sup> + 4 H<sup>+</sup> + 3 e === > NO + 2 H<sub>2</sub>O ... Ered = + 0.957 V

So it appears that nitric acid cannot oxidise Tl(I) to Tl(III). But aqua regia contains nitrosyl chloride (NOCl), a much more powerful oxidiser.

[Edited on 16-1-2014 by blogfast25]

zephler1 - 16-1-2014 at 17:10

Thanks for your post blogfast25; unfortunately that reaction produces TlCl3, but I do appreciate the reference.

blogfast25 - 17-1-2014 at 13:37

Quote: Originally posted by zephler1  
unfortunately that reaction produces TlCl3, but I do appreciate the reference.


Not really. It produces a solution that contains Tl<sup>3+</sup>, nitrate, chloride, hydronium and water.

Treatment with NH3 solution should yield Tl(OH)3 which could theb be re-dissolved into nitric acid to yield Tl(NO3)3.