Chapter 9.5, Problem 11CC

 (a)

Interpretation Introduction

Interpretation:

The reagents used to accomplish the given transformation should be draw and identified.

Concept Introduction:

Platinum reduction reaction: The alkenes can be reduced to alkanes with ${\text{H}}_{\text{2}}$ in the presence of metal catalyst (Pt). The two new $\text{C-H σ}$ bonds are formed simultaneously from $\text{H}$ atoms absorbed into the metal surface. Further this type of reaction stereospecific giving only the cis (syn) addition product.

Linder’s catalyst (Pt/H₂): The alkyne reduced to alkenes to give the cis $\left(Z\right)$ alkene.

Metal and ammonia reaction: The conjugated alkynes and benzenes in the presence of sodium metal in liquid ammonia and alkyne produced a non-conjugated diene system. The alkyne involves sodium $\left(\text{Na}\right){\text{/NH}}_{\text{3}}$. This end up reducing to alkyne to give the trans $\left(\text{E}\right)$ alkene.

(b)

Interpretation Introduction

Interpretation:

The reagents used to accomplish the given transformation should be draw and identified.

Concept Introduction:

Platinum reduction reaction: The alkenes can be reduced to alkanes with ${\text{H}}_{\text{2}}$ in the presence of metal catalyst (Pt). The two new $\text{C-H σ}$ bonds are formed simultaneously from $\text{H}$ atoms absorbed into the metal surface. Further this type of reaction stereospecific giving only the cis (syn) addition product.

Linder’s catalyst (Pt/H₂): The alkyne reduced to alkenes to give the cis $\left(Z\right)$ alkene.

Metal and ammonia reaction: The conjugated alkynes and benzenes in the presence of sodium metal in liquid ammonia and alkyne produced a non-conjugated diene system. The alkyne involves sodium $\left(\text{Na}\right){\text{/NH}}_{\text{3}}$. This end up reducing to alkyne to give the trans $\left(\text{E}\right)$ alkene.