How will you bring out the following conversions ?
Ethyne to but-2-yne

Explanation

How will you convert the following
Ethyne to but -2-yne: Ethyne reacts with strong base `NaNH_(2)`, forming sodium alkynide. Then on reaction with methyl bromide forms but -2-yne.
`underset("Ethyne")(CH-= CH) underset(-2NH_(3))overset(2NaNH_(2))rarr overset(+)(N) a overset(-)(C )-= overset(-)(C ) overset(+)(N)a underset(-2NaBr)overset(2CH_(3)Br)rarr CH_(3)- underset("but-2-yne")(C-= C)- CH_(3)`