Advertisements
Advertisements
प्रश्न
Why does acetylation of –NH2 group of aniline reduce its activating effect?
उत्तर
Direct nitration of aniline is not possible on account of oxidation of –NH2 group. However, nitration can be carried after protecting the –NH2 group by acetylation to give acetanilide which is then nitrated and finally hydrolysed to give o- and p-nitroanilines.
The acetyl group being electron-withdrawing attracts the lone pair of electrons of the N-atom towards carbonyl group.
As a result, the activating effect –NH2 group is reduced i.e., the lone pair of electrons on nitrogen is less available for donation to benzene ring by resonance. Therefore, activating effect of –NHCOCH3 group is less than that of –NH2 group.
APPEARS IN
संबंधित प्रश्न
Why is benzene diazonium chloride not stored and is used immediately after its preparation?
Match the compounds given in Column I with the items given in Column II.
| Column I | Column II | ||
| (i) | Benzene sulphonyl chloride | (a) | Zwitter ion |
| (ii) | Sulphanilic acid | (b) | Hinsberg reagent |
| (iii) | Alkyl diazonium salts | (c) | Dyes |
| (iv) | Aryl diazonium salts | (d) | Conversion to alcohols |
A colourless substance ‘A’ \[\ce{(C6H7N)}\] is sparingly soluble in water and gives a water soluble compound ‘B’ on treating with mineral acid. On reacting with \[\ce{CHCl3}\] and alcoholic potash ‘A’ produces an obnoxious smell due to the formation of compound ‘C’. Reaction of ‘A’ with benzenesulphonyl chloride gives compound ‘D’ which is soluble in alkali. With \[\ce{NaNO2}\] and \[\ce{HCl}\], ‘A’ forms compound ‘E’ which reacts with phenol in alkaline medium to give an orange dye ‘F’. Identify compounds ‘A’ to ‘F’.
Which of the following is true characteristic feature of aniline?
Which of the following is the most stable diazonium salt?
Benzene diazonium chloride is a ______.
Consider the following compounds:
(i) p-methyl aniline
(ii) N, N-dimethylaniline
(iii) N-ethyl aniline
(iv) N-ethyl-N-methyl aniline
The compounds which do not form diazonium salt with ice-colds NaNO2 and HCl are:
Major Product In the above chemical reaction, intermediate "X" and reagent/condition "A" are:
Aniline dissolved in dilute HCl is reacted with sodium nitrate at 0 °C. This solution was added dropwise to a solution containing equimolar mixture of aniline and phenol in dil. HCl. The structure of the major product is:
How will the following be converted? (Give chemical equation)
Aniline to benzene diazonium chloride.
