Na in liquid NH3 reduces but-2-yne mainly to

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NEET levelSingle correct optionDifficulty 1 of 3ro167

Na in liquid $NH X_{3}$ reduces but-2-yne mainly to

Abutane
Bcis-but-2-ene
Ctrans-but-2-ene
Dbut-1-ene

Answer: C

Dissolving metal reduction of an internal alkyne proceeds through a vinyl radical anion and a vinyl anion that prefers the trans geometry. Protonation therefore gives the trans alkene, and the alkene is not reduced further.

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Na in liquid NHX3​ reduces but-2-yne mainly to

Answer: C

More questions on Dissolving metal reductions (Birch, Na/NH3)

Na in liquid $NH X_{3}$ reduces but-2-yne mainly to