Discussion Forum



1)

The trans- alkenes are formed by the reduction of alkynes with


A) $H_{2}-Pd/C,BaSO_{4}$

B) $NaBH_{4}$

C) $Na/liq.NH_{3}$

D) $Sn-HCL$

Answer:

Option C

Explanation:

Sodium metal in liquid  ammonia reduces alkynes with anti stereochemistry to give trans alkenes.The reduction is selectively anti since the vinyl radical formed during reduction is more stable in trans configuration.

Mechanism

 482019800_vinyl.JPG