Q. The synthesis of 3-octyne is achieved by adding a bromoalkane into a mixture of sodium amide and an alkyne. The bromoalkane and alkyne respectively are
A) $BrCH_{2}CH_{2}CH_{2}CH_{2}CH_{3}\ and\ CH_{3}CH_{2}C \equiv CH$
B) $BrCH_{2}CH_{2}CH_{3}\ and\ CH_{3}CH_{2}CH_{2}C \equiv CH$
C) $BrCH_{2}CH_{2}CH_{2}CH_{2}CH_{3}\ and\ CH_{3}C \equiv CH$
D) $BrCH_{2}CH_{2}CH_{2}CH_{3}\ and\ CH_{3}CH_{2}C \equiv CH$
Explanation
(d)
3-octyne is obtained by the reaction of 1-bromobutane and but-1-yne in presence of sodamide.
$CH_{3}CH_{2}C \equiv CH + NaNH_{2}$
$\rightarrow CH_{3}CH_{2} - C \equiv \overline{C}Na^{+}$
$CH_{3}CH_{2}C \equiv \overline{C}Na + BrCH_{2}CH_{2}CH_{2}CH_{3}$
$\rightarrow CH_{3}CH_{2}C \equiv C - CH_{2}CH_{2}CH_{2}CH_{3}$
3-octyne
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.