Chapter 14, Problem 14.14P

Interpretation Introduction

(a)

Interpretation:

The product formed when $\text{3-hexyne}$ is treated with sodium in liquid ammonia is to be stated. Also, the product formed when the product of the above reaction is treated with ${\text{D}}_{\text{2}}$ over $\text{Pd/C}$ is to be stated.

Concept introduction:

Alkynes are reduced to trans-alkenes on reaction with sodium in liquid ammonia. This reaction takes place in two steps. In first step, a radical anion is formed which abstracts a proton from ammonia to form a vinylic radical. In the second step, vinylic radical undergoes inversion and abstracts a proton from ammonia to form a trans-alkene.

Interpretation Introduction

(b)

Interpretation:

The product formed when $\text{3-hexyne}$ is treated with hydrogen over $\text{Pd/C}$ and quinoline is to be stated. The product formed when product of that reaction is treated with ${\text{D}}_{\text{2}}$ over $\text{Pd/C}$ is to be stated.

Concept introduction:

Alkynes react with hydrogen over $\text{Pd/C}$ and quinoline to give cis-alkenes. This type of reaction is hydrogenation reaction. The alkenes are reduced to deuterated alkanes when treated with ${\text{D}}_{\text{2}}$ over $\text{Pd/C}$.