# Trans-hydroxylation of alkenes

In the trans-hydroxylation of alkenes to give alcohols, there is a formation of epoxide.

Does the reaction stop here if we don't add water?

Even though if we add water, why does the product depends on which medium the reaction is carried whether acidic or basic? My text says the ring opens differently for basic and acidic medium, but both finally gives us a trans-vicinal-diol.

• Oxiranes are stable in neutral water solutions and can be easly isolated. – Mithoron Jun 3 '15 at 15:53
• You can stop the reaction at the epoxide. It even has its own name: the Prilezhaev Reaction (the spelling may vary). – Philipp Jun 3 '15 at 17:35
• Concerning the ring opening have a look here. – Philipp Jun 3 '15 at 17:39
• There are many natural products out there that contain an epoxide ring (in cellular, i.e. aquatic environments) and many total syntheses of these that create the epoxide at a rather early stage and keep it through the remainder of the synthesis. – Jan Jun 4 '15 at 1:10

And finally, there are even methods out there to turn vicinal diols into epoxides (usually via sulphonylation, e.g. to a tosylate followed by intramolecular $\mathrm{S_N}2$ reaction).