Q. The reduction of an alkyne to alkene using lithium metal in liquid ammonia as solvent results into
A) $cis$ addition of hydrogen atoms
B) $trans$ addition of hydrogen atoms
C) Both $cis$ and $trans$ additions of hydrogen atoms. The relative amounts of the two depends on temperature
D) Both $cis$ and $trans$ additions of hydrogen atoms. The relative amounts depend on the nature of alkyne
Explanation
(b)
For $trans$product we take Na/liquid $NH_{3}$ or $Li - NH_{3}/C_{2}H_{5}OH$ or $LiAlH_{4}$ as a reducing agnet ($anti$-addition)
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.