The amine that reacts with Hinsberg’s reagent to give an alkali insoluble product is [2019]
[IMAGE 308]
[IMAGE 309]
[IMAGE 310]
[IMAGE 311]
(1)
Secondary amines on reaction with Hinsberg’s reagent give N, N-dialkylbenzene sulphonamide which does not contain any hydrogen atom attached to N-atom, it is not acidic and hence, insoluble in alkali. Tertiary amines do not react with Hinsberg’s reagent. Primary amines give products which are soluble in alkali.
Nitration of aniline in strong acidic medium also gives m-nitroaniline because [2018]
inspite of substituents nitro group always goes to only m-position
in electrophilic substitution reactions amino group is meta directive
in absence of substituents nitro group always goes to m-position
in acidic (strong) medium aniline is present as anilinium ion.
(4)
[IMAGE 312]
The reason for formation of an unexpected amount of m-nitroaniline is that under strongly acidic condition of nitration, most of the aniline is converted into anilinium ion and since, – is a m-directing group, therefore, a large amount of m-nitroaniline is also obtained.
The correct increasing order of basic strength for the following compounds is [2017]
[IMAGE 313]
III < I < II
III < II < I
II < I < III
II < III < I
(3)
effect of substituted group increases the basic strength while effect of substituent decreases the basic strength of aniline.
The correct statement regarding the basicity of arylamines is [2016]
arylamines are generally more basic than alkylamines because of aryl group
arylamines are generally more basic than alkylamines, because the nitrogen atom in arylamines is sp-hybridised
arylamines are generally less basic than alkylamines because the nitrogen lone-pair electrons are delocalised by interaction with the aromatic ring -electron system
arylamines are generally more basic than alkylamines because the nitrogen lone-pair electrons are not delocalised by interaction with the aromatic ring -electron system.
(3)
In arylamines, lone pair of electrons on nitrogen atom is delocalised over the benzene ring, thus, not available for donation. So, arylamines are less basic than alkylamines.
