The synthesis of 3-octyne is achieved by adding a bromoalkane into a mixture of sodium amide and an alkyne. The bromoalkane and alkyne respectively are:

CH3−CH2−C≡CH + NaNH2 → CH3−CH2−C≡C−Na+ + NH3

CH3−CH2−C≡C−Na+ + BrCH2CH2CH2CH3 → CH3−CH2−C≡C−CH2CH2CH2CH3 + NaBr

The reaction involves the deprotonation of the terminal alkyne (CH3CH2C≡CH) by sodium amide (NaNH2) to form an acetylide anion. This anion then undergoes a nucleophilic substitution reaction with the bromoalkane (BrCH2CH2CH2CH3) to form 3-octyne.