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Match Reaction Sequences with Resulting Phenolic Compounds

List-I contains various reaction sequences and List-II contains different phenolic compounds. Match each entry in List-I with the appropriate entry in List-II and choose the correct option.

Question Diagram 1

Options

A

P-2, Q-3, R-4, S-5

B

P-2, Q-3, R-5, S-1

C

P-3, Q-5, R-4, S-1

Correct
D

P-3, Q-2, R-5, S-4

Step-by-Step Solution

To determine the correct matching between the reaction sequences in List-I and the resulting phenolic compounds in List-II, we analyze each reaction sequence step-by-step:


Reaction Sequence (P)

  1. Step (i): Benzenesulfonic acid (C6H5SO3H\text{C}_6\text{H}_5\text{SO}_3\text{H}) undergoes alkali fusion with molten NaOH\text{NaOH} followed by acidification with H3O+\text{H}_3\text{O}^+ to yield phenol (C6H5OH\text{C}_6\text{H}_5\text{OH}).
  2. Step (ii): Nitration of phenol with Conc. HNO3\text{Conc. HNO}_3 results in electrophilic aromatic substitution at all activated ortho and para positions (2, 4, and 6) to yield 2,4,6-trinitrophenol (Picric acid).
Ph-SO3Hmolten NaOH, H3O+Ph-OHConc. HNO32,4,6-trinitrophenol\text{Ph-SO}_3\text{H} \xrightarrow{\text{molten NaOH, } \text{H}_3\text{O}^+} \text{Ph-OH} \xrightarrow{\text{Conc. HNO}_3} \text{2,4,6-trinitrophenol}
  • Result: Matches with compound (3).

Reaction Sequence (Q)

  1. Step (i): Nitration of nitrobenzene (C6H5NO2\text{C}_6\text{H}_5\text{NO}_2) using Conc. HNO3/Conc. H2SO4\text{Conc. HNO}_3 / \text{Conc. H}_2\text{SO}_4 directs the incoming nitro group to the meta-position, giving 1,3-dinitrobenzene.
  2. Step (ii): Reduction with Sn/HCl\text{Sn/HCl} converts both nitro groups into amino groups, forming benzene-1,3-diamine (mm-phenylenediamine).
  3. Step (iii): Diazotization using NaNO2/HCl\text{NaNO}_2 / \text{HCl} at 05 C0 - 5\ ^\circ\text{C} converts both amino groups into diazonium salts, yielding benzene-1,3-bis(diazonium) chloride.
  4. Step (iv): Boiling with H2O\text{H}_2\text{O} hydrolyzes the diazonium groups to hydroxyl groups, yielding benzene-1,3-diol (Resorcinol).
  5. Step (v): Nitration of resorcinol with Conc. HNO3/Conc. H2SO4\text{Conc. HNO}_3 / \text{Conc. H}_2\text{SO}_4 occurs at positions 2, 4, and 6, which are all strongly activated by both OH-\text{OH} groups, yielding 2,4,6-trinitrobenzene-1,3-diol (Styphnic acid).
NitrobenzeneNitration1,3-DinitrobenzeneSn/HClBenzene-1,3-diamineNaNO2/HClBis-diazonium saltH2OResorcinolNitration2,4,6-Trinitrobenzene-1,3-diol\text{Nitrobenzene} \xrightarrow{\text{Nitration}} \text{1,3-Dinitrobenzene} \xrightarrow{\text{Sn/HCl}} \text{Benzene-1,3-diamine} \xrightarrow{\text{NaNO}_2/\text{HCl}} \text{Bis-diazonium salt} \xrightarrow{\text{H}_2\text{O}} \text{Resorcinol} \xrightarrow{\text{Nitration}} \text{2,4,6-Trinitrobenzene-1,3-diol}
  • Result: Matches with compound (5).

Reaction Sequence (R)

  1. Step (i): Sulfonation of resorcinol (benzene-1,3-diol) with Conc. H2SO4\text{Conc. H}_2\text{SO}_4 occurs preferentially at positions 4 and 6 due to steric hindrance at position 2 (between the two OH-\text{OH} groups), yielding benzene-1,3-diol-4,6-disulfonic acid.
  2. Step (ii): Nitration with Conc. HNO3\text{Conc. HNO}_3 introduces a nitro group at the remaining vacant, activated position 2, forming 2-nitrobenzene-1,3-diol-4,6-disulfonic acid.
  3. Step (iii): Heating with acid (H3O+,Δ\text{H}_3\text{O}^+, \Delta) hydrolyzes and removes both sulfonic acid groups (desulfonation), selectively yielding 2-nitrobenzene-1,3-diol (2-nitroresorcinol).
ResorcinolConc. H2SO4Benzene-1,3-diol-4,6-disulfonic acidConc. HNO32-Nitrobenzene-1,3-diol-4,6-disulfonic acidH3O+,Δ2-Nitrobenzene-1,3-diol\text{Resorcinol} \xrightarrow{\text{Conc. H}_2\text{SO}_4} \text{Benzene-1,3-diol-4,6-disulfonic acid} \xrightarrow{\text{Conc. HNO}_3} \text{2-Nitrobenzene-1,3-diol-4,6-disulfonic acid} \xrightarrow{\text{H}_3\text{O}^+, \Delta} \text{2-Nitrobenzene-1,3-diol}
  • Result: Matches with compound (4).

Reaction Sequence (S)

  1. Step (i): Oxidation of toluene (C6H5CH3\text{C}_6\text{H}_5\text{CH}_3) with alkaline KMnO4,Δ\text{KMnO}_4, \Delta followed by acid workup (H3O+\text{H}_3\text{O}^+) yields benzoic acid.
  2. Step (ii): Nitration of benzoic acid under vigorous conditions (Conc. HNO3/Conc. H2SO4,Δ\text{Conc. HNO}_3 / \text{Conc. H}_2\text{SO}_4, \Delta) introduces two nitro groups at both meta-positions, yielding 3,5-dinitrobenzoic acid.
  3. Step (iii): Reaction with SOCl2\text{SOCl}_2 followed by NH3\text{NH}_3 converts the acid group to an amide, producing 3,5-dinitrobenzamide.
  4. Step (iv): Hofmann bromamide degradation using Br2/NaOH\text{Br}_2 / \text{NaOH} converts the amide group to a primary amine, yielding 3,5-dinitroaniline.
  5. Step (v): Diazotization with NaNO2/HCl\text{NaNO}_2 / \text{HCl} at 05 C0 - 5\ ^\circ\text{C} forms 3,5-dinitrobenzenediazonium chloride.
  6. Step (vi): Hydrolysis by heating with H2O\text{H}_2\text{O} replaces the diazonium group with OH-\text{OH}, yielding 3,5-dinitrophenol.
TolueneKMnO4/KOH, H3O+Benzoic acidNitration, Δ3,5-Dinitrobenzoic acidSOCl2,NH33,5-DinitrobenzamideBr2/NaOH3,5-DinitroanilineNaNO2/HClDiazonium saltH2O3,5-Dinitrophenol\text{Toluene} \xrightarrow{\text{KMnO}_4/\text{KOH, } \text{H}_3\text{O}^+} \text{Benzoic acid} \xrightarrow{\text{Nitration, } \Delta} \text{3,5-Dinitrobenzoic acid} \xrightarrow{\text{SOCl}_2, \text{NH}_3} \text{3,5-Dinitrobenzamide} \xrightarrow{\text{Br}_2/\text{NaOH}} \text{3,5-Dinitroaniline} \xrightarrow{\text{NaNO}_2/\text{HCl}} \text{Diazonium salt} \xrightarrow{\text{H}_2\text{O}} \text{3,5-Dinitrophenol}
  • Result: Matches with compound (1).

Conclusion:

  • P \rightarrow 3
  • Q \rightarrow 5
  • R \rightarrow 4
  • S \rightarrow 1

Thus, the correct option is C.

Match Reaction Sequences with Resulting Phenolic Compounds | Chemistry PYQ Solution - JEE Challenger