# Does a certain “Badecker reaction” actually exist?

A book I read, mentions a certain Badecker reaction under coordination chemistry. It goes like this:

$$\ce{Na2[Fe (CN)5 NO] + Na2SO3 -> Na4[Fe (CN)5 (NOSO3)]}$$

I googled up the name, but I didn't get anything even remotely related to chemistry.

That particular book does have a pretty long history of typos and a couple of factual errors here and there (but I still use it because its got quite a few useful tips …)

So the question is; is there such a thing called the Badecker reaction (I even tried googling it up with an umlaut, Bädecker reaction, because, well … Badecker looks a little German, but then I was directed to a Wikipedia page on cadmium oxide. So what is the reaction’s name?

Also even if it doesn't go by that name, does the reaction actually even exist?

• Searched for you in my mother tongue german, but had no success as well. Maybe try finding this specific reaction searching for the complex sodium nitroprusside. – AstronAUT Aug 30 '16 at 17:06

The reaction in question is actually called the Boedeker reaction. How the book came from Boedeker to Badeker I do not know, but maybe there was one instance of Boedeker being written Bödeker which was later misparsed by a human or a robot and mistook for an a. (Replacing oe for ö is a common mistake with German names since the latter is typically used in orthography but names don’t adhere to orthography.)

The reaction is well-known and often used as a qualitative analysis for sulphite ions in solution, much like the same nitroprusside ion can also be used to detect sulphide ions. In chemical formulae, it is:

$$\ce{[Fe(CN)5(NO)]^2- + SO3^2- <=> [Fe(CN)5(NOSO3)]^4-}$$

The reaction in itself is also rather interesting since for over 100 years the structure of the addition complex was unknown. Bottomley et al. were finally able to obtain crystal structures of the probably structurally similar ruthenium complex $\ce{[RuCl(bpy)2(NOSO3)]}$.[1] These show that the addition product is — very much like in the sulphide case — formed by nucleophilic attack of the sulphite sulphur’s lone pair to nitrosyl nitrogen creating a nitrosylsulphite anion $\ce{O3SNO-}$. Thus, the complex formed should be named pentacyanidonitrosylsulphito-κN-ferrate(II).

Reference:
[1]: F. Bottomley, W. V. F. Brooks, D. E. Paéz, P. S. White, M. Mukida, J Chem. Soc., Dalton Trans. 1983, 2465. DOI: 10.1039/DT9830002465.

• Slightly OT: "but names don’t adhere to orthography.": this is a misconception of orthography, the orthography of names like of anything else is only a matter of definition. The definitions might show some regular behaviour, but thats essentially random. – Rudi_Birnbaum Jun 10 '17 at 17:23