# Does Wurtz reaction follow an ionic mechanism or a free radical mechanism?

In a Wurtz reaction, is the intermediate formed a carbanion or a free radical?

And if we can assume both mechanisms to be true, how can we decide the reactivity of a tertiary halide?

• I think your second question is fine as is. But, in the context of your first question, I just want to verify for myself that you do mean overall reactivity of a tertiary halide via the Wurtz reaction, irrespective of reaction pathway, and that you are not asking whether the reactivity will be dominated by carbanion-forming v.s. free-radical forming pathways. Wow, ancient question ;) I hope we can lead you to an acceptable answer! – airhuff Jan 13 '17 at 2:48

The essential thing to note is that the mechanism involves a $$\mathrm{S_N2}$$ step. And because of that sterically hindered alkyl halides, like tertiary alkyl halides, instead of giving a substitution product yield an elimination product and you get an alkene.