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In the reaction H−C≡CH (1)NaNH2/liq.NH3 (2)CH3CH2Br → X and Y are

1. X = 1-Butyne; Y = 3-Hexyne
2. X = 2-Butyne; Y = 3-Hexyne
3. X = 2-Butyne; Y = 2-Hexyne
4. X = 1-Butyne; Y = 2-Hexyne

Correct answer: X = 1-Butyne; Y = 3-Hexyne

Solution

The reaction involves deprotonation of terminal alkyne by NaNH2 to form an acetylide ion, which then undergoes nucleophilic substitution with CH3CH2Br to form 1-butyne. Further reaction with another equivalent of CH3CH2Br gives 3-hexyne.

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