Question

$B \stackrel{\text { Lindlar/ } H _{2}}{\leftarrow} R C \equiv CR \stackrel{\text { Na/liq.NH }_{3}}{\longrightarrow } A, A$ and $B$ are geometrical isomers $(R- CH = CH -R)$ then

• A. $A$ is cis, $B$ is trans
• B. $A$ is trans, $B$ is cis
• C. $A$ and $B$ both are $cis$
• D. $A$ and $B$ both are trans

Answer 1

Answer: (B)

Lindlar's catalyst gives cis product thus $B$ is cis and Na/liq. $NH _{3}$ give trans product. Thus $A$ is trans.