# Can aniline autodeprotonate?

I had an argument with an assistant in my lab, as he stated that in a hypothetical reaction two aniline molecules could react in a way, that one takes a proton off of the other one, thus creating a $\ce{R-NH3^+}$ and a $\ce{R-NH^- }$

However, the $\mathrm pK_\mathrm a$ of aniline is 27, which means, that it is, if at all, a very very poor acid, making it in my eyes impossible to deprotonate. Maybe it could be possible with n-BuLi, but that was not part of the reaction. The main topic was a nucleophilic aromatic substitution to 1-bromo-4-nitrobenzene, with aniline.

Is it even hypothetically possible for such a deprotonation in pure aniline to occur?

• Looks you're right. – Mithoron Nov 7 '17 at 18:13
• Deprotonation of very weak acids is still very much possible; that's how their pKa's came to be known in the first place. But yes, that would take BuLi or something comparable, which you say you didn't use. – Ivan Neretin Nov 7 '17 at 21:14