Question: Devise a synthesis of each compound using CH₃CH₂CH=CH₂as the starting material. You may use any other compounds or inorganic reagents.

a.

b.

c.

d.

e.

(+ enantiomer)

Alkynes are reactive due to the presence of an easily breakable bond. Terminal alkynes are reactive in nature due to the highly acidic carbon-hydrogen bonds.

Alkynes can undergo a variety of reactions. They can undergo addition reactions because of the presence of a weak bond.

The acetylide anions which are formed by the loss of a proton from terminal alkynes are strong nucleophiles and react with a variety of electrophiles.

Due to the strong nucleophilic nature of the acetylide anions, they are able to react with epoxide and undergo the opening of the epoxide rings.

The alkyne${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{C}\equiv \mathrm{CH}$can be prepared by the halogenation reaction of the alkene${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{CH}={\mathrm{CH}}_2$, i.e., but-1-ene. In the next step, the vicinal dihalide is treated with a strong base to produce the desired alkyne.

The acetylide ion is then treated with the epoxide to produce the desired compound, as shown below:

Formation of hex-3-yne-1-ol

Formation of + enantiomer