Learn

Saturday, 31 October

JEE Main 2024 · ChemistryMultiple choiceSingle correctHardApplication

JEE Main 9 April 2024, Shift 2, Chemistry Q75

Question 75 of 90 in this shift, Chemistry question 15 of 30, Section A.

[figure: C6H5−CH(CH3)−CH(OCH3)−Br\mathrm{C_6H_5-CH(CH_3)-CH(OCH_3)-Br} (benzylic carbon bearing CH3_3, next carbon bearing both OCH3_3 and Br)] →ΔKCN (alc)\xrightarrow[\Delta]{\mathrm{KCN\ (alc)}} Major Product 'P' In the above reaction product 'P' is

The figure, in words

Skeletal structure: phenyl ring attached to a carbon bearing a CH3 (drawn upward); the next carbon bears Br (drawn upper right) and OCH3 (drawn downward). Reagent KCN (alc), heat. Options are skeletal structures with CN, CH3, OCH3 and phenyl placed as described in each option.
  1. (1)[figure: C6H5−C(CH3)(CN)−CH2−OCH3\mathrm{C_6H_5-C(CH_3)(CN)-CH_2-OCH_3}]
  2. (2)[figure: C6H5−CH(CH3)−CH(CN)−OCH3\mathrm{C_6H_5-CH(CH_3)-CH(CN)-OCH_3}]Official answer
  3. (3)[figure: C6H5−CH(CN)−CH(CH3)−OCH3\mathrm{C_6H_5-CH(CN)-CH(CH_3)-OCH_3}]
  4. (4)[figure: C6H5−CH(OCH3)−CH(CH3)−CN\mathrm{C_6H_5-CH(OCH_3)-CH(CH_3)-CN}]

Official answer

Option 2

NTA final key.

Chapter
Haloalkanes and Haloarenes
Topic
SN1 and SN2 Mechanisms
Idea tested
Ambident Nucleophiles (Cyanide/Nitrite)

Same idea in other shifts

Asked 4× in all
  1. 13 Apr 2023, Shift 2 · Q75Match List I with List II 1 - Bromopropane is reacted with reagents in List I to give product in List II LIST I - Reagent | LIST II -…MediumMatch the list
  2. 17 Mar 2021, Shift 2 · Q43The correct pair(s) of the ambident nucleophiles is (are) : (A) AgCN/KCN\mathrm{AgCN/KCN} (B) RCOOAg/RCOOK\mathrm{RCOOAg/RCOOK} (C)…MediumOther
  3. 18 Mar 2021, Shift 2 · Q42Given below are two statements : Statement I : C2H5OH\mathrm{C_2H_5OH} and AgCN both can generate nucleophile. Statement II : KCN and AgCN…MediumTwo statements

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 108 of the 174 JEE Main shifts held from 2017 to 2026.