Manganates

[budullewraagh]

we all know permanganates exist, but little is said/found of manganates. seriously. do a search online for manganates and all you will find are manganate (VII) which are really just permanganates. i found one site that mentioned the electrolytic oxidation of manganates...but theyre not even listed in the merck index and i cant find them on chemfinder. anybody know why theyre so elusive?

[Tetrahedrite]

I can answer that. The common oxidation states for Mn are 0, +2, +3, +4, +6, and +7. Starting from the bottom, Mn(0) is obviously metallic manganese. Mn2+ is most stable as the isolated Mn2+(aq) ion and therefore doesn't bond with oxygen to form manganates. Mn3+ is fairly unstable and usually reverts back to Mn2+. Mn4+ is extremely stable with oxygen, but doesn't form ions, it forms the solid MnO2 (pyrolusite is its mineral name). The manganate ion MnO4 2- (which is Mn6+) does exist but only forms in a very narrow eH range and is therefore not very common. And then Mn7+ is as you know the permanganate ion.

[budullewraagh]

i get moderately confused when there are such reactions involving permanganates oxidizing alcohols to organic acids though. got any idea of the reaction?