The most reactive amine towards dilute hydrochloric acid is ___________.
• 
being the strongest base among the given alkyl amines and interacts far better than towards dilute hydrochloric acid.
Reason being the presence of the 2 –CH3 groups on the adjacent carbon atoms which is more than (i) CH3—NH2 as the electron releasing + I effect pushes electron more effectively to N atom in case of 
.
• But the case of 
is contradictory because of steric factors. The N atom is surrounded by 3 bulky methyl groups which increases the chance for HCL protons to interact and bind to the unshared electron pairs on N atom, therefore, protonation is less effective here.
• 
being the least basic(conjugation of amino group with benzene ring) will be the least reactive towards HCL.