# Polar Protic and Aprotic Solvents

I know $$\mathrm{S_N2}$$ is favored polar aprotic solvents, which means that they may have hydrogens on them somewhere, but they lack $$\ce{O-H}$$ or $$\ce{N-H}$$ bonds, and therefore cannot hydrogen bond with themselves.

But I found that $$\mathrm{S_N2/E2}$$ is favored by $$\ce{OH-, RO-}$$ (a strong base); if I look at $$\ce{OH-}$$, doesn't it contain $$\ce{O-H}$$ and form hydrogen bonds?

Can someone please explain what aprotic solvents then? Are aprotic solvents a strong base? What's the difference between aprotic solvents and a strong base?

• OH- in what solvent? Powdered KOH in THF reacts in a very different way from KOH in MeOH. – Waylander Jun 16 at 16:52
• This was not mentioned . – Who Jun 16 at 16:56