13.4 Arrange the following:
(i) In decreasing order of the pKb values:
and
and are aliphatic amines so they are more basic than rest two compound. In ethylamine, there is only one electron donating group (+I effect) but in diethylamine, there is two electron donating group so the electron density is much higher than ethylamine.
In between and they are the weak base because of delocalisation of lone pair electron in the benzene ring. Aniline is less basic than N-methylaniline() due to the absence of an electron donating group. Thus the decreasing order of pKb values is-