Learn

Friday, 9 October

JEE Main 2024 · ChemistryMultiple choiceDiagram basedMediumApplication

JEE Main 8 April 2024, Shift 1, Chemistry Q78

Question 78 of 90 in this shift, Chemistry question 18 of 30, Section A.

Identify the major products A and B respectively in the following set of reactions. [figure: 1-methylcyclohexan-1-ol (ring carbon bearing CH3 and OH); with conc. H2SO4\mathrm{H_2SO_4}, Δ\Delta giving A; with CH3COCl\mathrm{CH_3COCl}, pyridine giving B]

The figure, in words

Reaction scheme: 1-methylcyclohexanol in the centre; right arrow labelled conc. H2SO4, heat gives A; left arrow labelled CH3COCl / pyridine gives B. Options give structures for A and B.
  1. (1)A = [figure: methylenecyclohexane] and B = [figure: cyclohexane ring carbon bearing CH3\mathrm{CH_3}, OH and COCH3\mathrm{COCH_3}]
  2. (2)A = [figure: 1-methylcyclohexene] and B = [figure: cyclohexane ring carbon bearing CH3\mathrm{CH_3} and OCOCH3\mathrm{OCOCH_3}]Official answer
  3. (3)A = [figure: 1-methylcyclohexene] and B = [figure: 4-acetyl-1-methylcyclohexan-1-ol (CH3CO\mathrm{CH_3CO} para to the C bearing CH3\mathrm{CH_3} and OH)]
  4. (4)A = [figure: methylenecyclohexane] and B = [figure: cyclohexane ring carbon bearing CH3\mathrm{CH_3} and COCH3\mathrm{COCH_3}]

Official answer

Option 2

NTA final key.

Chapter
Alcohols, Phenols and Ethers
Topic
Alcohols and Phenols
Idea tested
Alcohol Dehydration Ease

Same idea in other shifts

Asked 2× in all
  1. 5 Apr 2026, Shift 1 · Q67Consider compounds A, B and C with following structural formulae A = CH3−CH2−CH2−CH2−CH2−OH\mathrm{CH_3-CH_2-CH_2-CH_2-CH_2-OH} B =…EasyOtherHas a figure

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. This question needs a figure we do not reproduce; it is described in words above. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.