Phenylnitromethane

[Explosives Chemist]

Is it possible to nitrate Phenylnitromethane? C7H7NO2+ 3HNO3 ----> 3H2O + C7H4N4O8.

[kingspaz]

read the rules. no new topics with a low post count. however this could turn to be interesting so will remain open.

i think it should be possible. but only because i don't see any reason why it wouldn't be possible. most aromatics can be nitrated. i think the degree of nitration and orientation of the NO2 groups will depend however on the CH2NO2 groups nature when it comes to electron movement. i'm tempted to think it would with not withdraw electron density (dunno why i think that) so i think it would activate at 2,4,6.

[Mr Cool]

Hmmm... if it was just a methyl then it would be 2,4,6-, but I think the NO2 on the CH2 might be sufficiently electron withdrawing to suck electrons from the delocalisation, leading to 3,5-, despite the CH2 in the middle. It shouldn't be as bad as a plain NO2 though, so it'll be easier to nitrate than nitrobenzene.
I guess it'll go to (3,5-dinitrophenyl)nitromethane, a TNT isomer.
Could be wrong though.

If the alkyl chain with the NO2 on was longer, then the electron withdrawing properties of the NO2 would not have as much effect, thus it could go to 2,4,6-, but I think in this case it'll be 3,5- directing.

I'm also wondering about oxidation on the CH2 of the nitromethyl bit, but I don't think I could explain why I think it might get oxidised.

[kingspaz]

i was thinking the delocalised system cannot be extended due to the CH2 bit between the NO2 and the benzene ring since the CH2 bit is fully saturated so i thought the NO2's effect would be substantially reduced. i too initially thought the NO2 would activate 3,5 but it all depends on how much the CH2NO2 group is going to withdraw...:confused:

[vulture]

was thinking the delocalised system cannot be extended due to the CH2 bit between the NO2

True. There is no p orbital between the NO2 and the ring system so it can't be a part of the delocalized system.

[Mr Cool]

True, the delocalisation itself isn't extended, but the NO2 is still going to pull electron density away from the CH2, which in turn will pull electron density from the ring via the inductive effect. I'm not sure if that is enough to make it go 3,5- though. I've downloaded a book on aromatic reactivity, but have not yet read it :).