Which of the following statements about but-1-yne, HC#C-CH2CH3, are correct? Select all that apply.

H2O, HgSO4, H2SO4 gives butan-2-one

(i) NaNH2; (ii) CH3I gives pent-2-yne

H2 over Lindlar's catalyst gives but-1-ene

H2O, HgSO4, H2SO4 gives butan-2-one

(i) disiamylborane; (ii) H2O2/NaOH gives butan-2-one

(i) NaNH2; (ii) CH3I gives pent-2-yne

H2 over Lindlar's catalyst gives but-1-ene

MolSynapse / Question bank / Hydrocarbons / Alkynes: acidity, preparation and reactions

JEE Advanced levelOne or more correct optionsDifficulty 3 of 3hc088

Which of the following statements about but-1-yne, $HC \equiv C - CH X_{2} CH X_{3}$ , are correct? Select all that apply.

A $H X_{2} O$ , $HgSO X_{4}$ , $H X_{2} SO X_{4}$ gives butan-2-one
B(i) disiamylborane; (ii) $H X_{2} O X_{2} / NaOH$ gives butan-2-one
C(i) $NaNH X_{2}$ ; (ii) $CH X_{3} I$ gives pent-2-yne
D $H X_{2}$ over Lindlar's catalyst gives but-1-ene

Answer: A, C, D

Amide forms the acetylide, which is methylated at carbon to give

CH X_{3} CH X_{2} - C \equiv C - CH X_{3}

, pent-2-yne. Lindlar reduction stops at the alkene, giving but-1-ene. Markovnikov hydration gives butan-2-one. Hydroboration with a hindered borane followed by oxidation is anti-Markovnikov and gives the enol that tautomerises to butanal, not butan-2-one.

Practice Hydrocarbons More on Alkynes: acidity, preparation and reactions

Previous questionNext question

Which of the following statements about but-1-yne, HC≡C−CHX2​CHX3​, are correct? Select all that apply.

Answer: A, C, D

More questions on Alkynes: acidity, preparation and reactions

Which of the following statements about but-1-yne, $HC \equiv C - CH X_{2} CH X_{3}$ , are correct? Select all that apply.