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Friday, 9 October

JEE Main 2020 · ChemistryMultiple choiceSingle correctMediumApplication

JEE Main 8 January 2020, Shift 1, Chemistry Q39

Question 39 of 75 in this shift, Chemistry question 14 of 25, Section A.

The most suitable reagent for the given conversion is :

The figure, in words

Reaction scheme: a decalin (bicyclic saturated) bearing CONH2, C(=O)CH3, CN and CO2H substituents is converted (reagent '?') into the same decalin with CONH2, COCH3, CN unchanged and CO2H replaced by CH2OH (HOH2C).
  1. (1)LiAlH4\mathrm{LiAlH_4}
  2. (2)B2H6\mathrm{B_2H_6}Official answer
  3. (3)H2/Pd\mathrm{H_2/Pd}
  4. (4)NaBH4\mathrm{NaBH_4}

Official answer

Option 2

NTA final key (Jan 2020).

Chapter
Aldehydes, Ketones and Carboxylic Acids
Topic
Carboxylic Acids and Derivatives
Idea tested
Reduction of Acids

Same topic in other shifts

All Carboxylic Acids and Derivatives questions
  1. 5 Apr 2026, Shift 2 · Q65Complete the following reaction sequence and give the name of major product 'P'. CH3CH2C≡N\mathrm{CH_3CH_2C{\equiv}N}…MediumSingle correctHas a figure
  2. 8 Apr 2026, Shift 2 · Q67Consider the following reaction. [figure: N-substituted 2-piperidone (six-membered lactam, C=O adjacent to ring N) with N bonded to…HardDiagram basedHas a figure
  3. 2 Apr 2025, Shift 1 · Q67Consider the following molecules : (p) CH3−CH2−C(=O)−Cl\mathrm{CH_3-CH_2-C(=O)-Cl} (q) CH3−CH2−C(=O)−O−C(=O)−CH3\mathrm{CH_3-CH_2-C(=O)-O-C(=O)-CH_3} (r)…EasySingle correctHas a figure
  4. 2 Apr 2025, Shift 2 · Q68Consider the following reactions. From these reactions which reaction will give carboxylic acid as a major product ? (A)…MediumOtherHas a figure
  5. 8 Apr 2025, Shift 2 · Q69A→(ii) H3O+(i) NaOHB→(ii) H2SO4,Δ(i) EtOHCA \xrightarrow[\text{(ii) H}_3\text{O}^+]{\text{(i) NaOH}} B \xrightarrow[\text{(ii) H}_2\text{SO}_4, \Delta]{\text{(i) EtOH}} C 'A'…MediumSingle correctHas a figure
  6. 8 Apr 2024, Shift 1 · Q79Identify the product (P) in the following reaction: [figure: cyclopentanecarboxylic acid]…EasyDiagram basedHas 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.