BASF - 27-6-2003 at 08:30
Imagine a nitramine like RDX or HMX, or whatever.
The aza-functions of the ring are good lewis-bases!
A known cyclic aza-ligand is 1,4,7-triazacyclononane.
It is a 3-dent-ligand.
The orbitals used in coordination-compounds(d,f...) are not the same used as in normal organic compounds.
Ok. Let´s attach the usual three nitro-groups to it and then use its d-orbital-capacities to bond a transition metal which is itself bonded with
useful energetic functional groups, like nitroso, nitrate, azide or whatever.
Now we´ve obtained a super-dense, fuel-balanced molecule without losing much stability. The properties of this compound can easily be altered by
choosing another transition-metal.
So far i´ve never heard of compounds of exactly THIS kind.(although i am at least aware of the known DADNPyOx-complexes)
I fear this is because the nitro-groups on the aza-function are together with the ring-structure too much of a steric hindrance to allow an orthogonal
coordination-bond with a transition metal.
But what if the oxidizing functional group(-NO2) would be replaced with a smaller oxidizer like chlorine, or -NO?
I know this is very theoretical, but thinking is not forbidden, right?
HLR
AndersHoveland - 28-3-2012 at 17:53
I do not think this would work.
The nitramine groups in RDX cannot complex with metal ions because the nitrogen connected to the methylene groups is somewhat electron donating
towards the oxygen atoms (this is one of the things that helps stabilise nitramine explosives). In other words, there is already a partial positive
charge in the nitrogen. It is not going to bind to a similarly charged metal cation.
However, primary nitramines (such as ethylene dinitramine or methyl nitramine CH3NHNO2) can form complexes with transition metals.
The hydrogen atom can ionize off leaving an anion. This extra electron is what allows the molecule to bind.