Acetamide and ethyl amine can be distinguished by reacting with
(a) aq. HCl and heat
(b) aq. NaOH and heat
(c) acidified KMnO4
(d) bromine water
(b) When acetamide is heated with aq. NaOH it forms NH3 gas but ethylamine cannot form NH3.
CH3CONH2 + H2OCH3COONa + NH3
CH3CH2NH2 + H2O No reaction
Intermediates formed during the reaction of RCONH2 with Br2 and KOH are
(a) RCONHBr and RNCO
(b) RNHCOBr and RNCO
(c) RNHBr and RCONHBr
(a) The reaction, RCONH2 + Br2 + KOH RNH2
is known as Hofmann bromamide reaction. The mechanism of this is given as:
Aniline is reacted with bromine water and the resulting product is treated with an aqueous solution of sodium nitrite in presence of dilute hydrochloric acid. The compound so formed is converted into a tetrafluoroborate which is subsequently heated. the final product is
(d) -NH2 group is greatly activating group. Hence, a reaction takes place rapidly.
Which of the following is the strongest base ?
(a) Aliphatic amines are a stronger base than aromatic amines.
The basicity of amines is due to the nitrogen of the amine donating its lone pair of electrons. In aromatic amines, this lone pair is in conjugation(delocalized) with the aromatic ring. While in aliphatic mine this doesn't happen and thus the lone pair is ready to be donated.