Question: Which of the following is least basic?
$\left(\mathrm{CH}_{3} \mathrm{CO}\right) \ddot{\mathrm{NH}} \mathrm{C}_{2} \mathrm{H}_{s}$
$\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{3} \ddot{\mathrm{N}}$
$\left(\mathrm{CH}_{3} \mathrm{CO}\right)_{2} \ddot{\mathrm{NH}}$
$\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{2} \ddot{\mathrm{N}} \mathrm{H}$
Correct Option: , 4
Solution:
(Hence least basic)
(d) $\mathrm{CH}_{3}-\mathrm{CH}_{2}-\ddot{\mathrm{NH}}-\mathrm{CH}_{2}-\mathrm{CH}_{3}$; L.P. on Nitrogen is localised.