# Mechanism for alcohol synthesis via terminal acetylene reaction with sodium amide followed with epoxide and protonation

If anyone can give me some guidance here, it'd be much appreciated. I know the NaNH2 would dissociate and the NH2- base would deprotonate the terminal acetylene. I'm assuming the resultant product would act as some sort of nucleophile which would open the ring of the epoxide. The Na+ would form an ionic bond with the negatively polar oxygen after which the acid would protonate said oxygen, but I'm not entirely sure.

• The final structure is wrong. Count carbons. Missing a CH2. Sep 20, 2021 at 23:08

Basically, you are on the right track and answered the question. First, NaNH$$_2$$ is used as a base to deprotonate the terminal alkyne (see this Reagent Friday). Second, the generated nucleophile opens the epoxide in an S$$_\mathrm{N}$$2 fashion, usually adding to the lesser substituted carbon which in your case yields a quaternary alcohol after acidic workup (see also Opening of Epoxides With Acid).
(Note: Indeed you are missing the CH$$_\mathrm{2}$$-group where the nucleophile attacks in the final structure)