Sciencemadness Discussion Board

Other metal analogs of sodium nitroprusside

Boffis - 26-3-2020 at 02:45

The nitroprusside anion has iron at its core, it is pentacyanonitroferrate III - Fe(CN)5NO--

Do any other metals form similar cyanocomplexes contain the NO group? I did a search online and through my chemsitry books and found few examples (actually only 1 reference to a manganese complex.

Bedlasky - 26-3-2020 at 04:02

Hi.

I found some document which mentioned pentacyano-nitrosyl complexes of Cr, Mn, Fe and Co.

https://www.google.com/url?sa=t&source=web&rct=j&...

Boffis - 3-4-2020 at 00:15

Well Bedlasky's refrence has lead me to a legion of such complexes, some sound very interesting with metal valencies of 0 or even -1!! Apart from the once indicated by Bedlasky's ref there are also V, Ru and possibly Ni compounds too.

Many thanks Bedlasky!

By the way has anyone every tried preparing NO gas? It is usually prepared from dilute nitric acid and copper powder but it can also be prepared from sodium nitrite and hydroxylamine hydrochloride; ferrous sulphate and sodium nitrite etc. But which is the cleanest and simplest? I did a search on SM but references to nitric oxide are few.

[Edited on 3-4-2020 by Boffis]

mackolol - 3-4-2020 at 01:07

Quote: Originally posted by Boffis  

By the way has anyone every tried preparing NO gas? It is usually prepared from dilute nitric acid and copper powder but it can also be prepared from sodium nitrite and hydroxylamine hydrochloride; ferrous sulphate and sodium nitrite etc.
[Edited on 3-4-2020 by Boffis]


Reaction of sodium nitrite with hydroxylamine hydrochloride yields N2O gas in normal conditions.

Boffis - 3-4-2020 at 04:43

Ah yes you are correct Mackolol. Its interesting that hydroxylamine is used as a proxy for NO when preparing nitrosylcyano complexes.

Looks like I will go for the ferrous sulphate - sodium nitrite route.

woelen - 3-4-2020 at 06:37

I have good experience with NaNO2, FeSO4 and acid. You can use cheap technical grade FeSO4 for that purpose.

Boffis - 10-4-2020 at 09:04

@ woelen, does NO react quickly with atmospheric oxygen? What I am interested in is whether I need to purge the equipment with an inert gas before generating the gas?

dawt - 10-4-2020 at 09:49

@Boffis: You'll definitively have to purge the air from your setup first. When generating NO from NaNO2 you can see a front of brown NO2 moving through the apparatus until all the oxygen has been consumed.

Boffis - 28-4-2020 at 23:21

Well I tracked down a number of preparations for pentacyanonitrosylmetallates including the nickel, cobalt, manganese, chromium and vanadium examples. I also found a preparation for Dihydroxypentacyanonitrosylmolybdate ion too.

My first attempt was to prepare the potassium pentacyanonitrosylchromate I. This proved much easier than the hexacyanochromate III and it is much more stable.

Pentacyanonitrosylchromate 0.jpg - 56kB Crude K3Cr(CN)5NO.H2O


Pentacyanonitrosylchromate 1.jpg - 65kB Recrystallised product

I will post the preparation detail later.