In the following reaction sequence, X and Z respectively are:

Q: In the following reaction sequence, X and Z respectively are:

1. Propan-1-ol + PCl5 arrow CH3CH2CH2Cl + POCl3 + HCl X = POCl3. 2. Dehydrohalogenation with alc. KOH yields propene (Y = CH3CH=CH2). 3. Anti-Markovnikov addition of HBr in presence of peroxide (CH3COO)2 yields 1-bromopropane (Z = CH3CH2CH2Br). X = POCl3 and Z = CH3CH2CH2Br. PCl5 gives POCl3 side product (whereas PCl3 gives H3PO3). Peroxide + HBr guarantees terminal addition. Class 12 Chemistry: Alcohols, Phenols and Ethers

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Solution & Explanation

Related Formula

R-OH + PCl₅ arrow R-Cl + POCl₃ + HCl

CH₃-CH=CH₂ + HBr Peroxide CH₃CH₂CH₂Br

Core Logic

Propan-1-ol + $PCl₅ arrow CH₃CH₂CH₂Cl + POCl₃ + HCl X = POCl₃$ .
Dehydrohalogenation with alc. $KOH$ $KOH$ yields propene ( $Y = CH₃CH=CH₂$ $Y = CH_3CH=CH_2$).
Anti-Markovnikov addition of $HBr$ $HBr$ in presence of peroxide $(CH₃COO)₂$ $(CH_3COO)_2$ yields 1-bromopropane ( $Z = CH₃CH₂CH₂Br$ $Z = CH_3CH_2CH_2Br$).

Step 1: Final Identification

$X = POCl₃$ $X = POCl_3$ and $Z = CH₃CH₂CH₂Br$ $Z = CH_3CH_2CH_2Br$.

Pattern Recognition

$PCl₅$ $PCl_5$ gives $POCl₃$ $POCl_3$ side product (whereas $PCl₃$ $PCl_3$ gives $H₃PO₃$ $H_3PO_3$). Peroxide + $HBr$ $HBr$ guarantees terminal addition.

Chapter Mix

Class 12 Chemistry: Alcohols, Phenols and Ethers

Detailed solution pathway for Q52 — Multistep reaction sequence starting from propan-1-ol with PCl5 and peroxide addition.

More Alcohols, Phenols and Ethers Previous-Year Questions

Q46 neet_2024_05_may_morning Chemical Reactions and Conversions

Match List I with List II

List-I	List-II
A. $H₃C-CH(OH)-CH₃$ $H_3C-CH(OH)-CH_3$	(I) (i) Oleum; (ii) $NaOH, Δ$ $NaOH, \Delta$; (iii) $H^+$ $H^+$
B. $CH₃COOH arrow CH₃CH₂OH$ $CH_3COOH \rightarrow CH_3CH_2OH$	(II) (i) $O₂$ $O_2$; (ii) $H₂O/H^+$ $H_2O/H^+$
C. $CH₃CH₂CH₂OH arrow CH₃CH(OH)CH₃$	(III) (i) $CH₃OH, H^+$ $CH_3OH, H^+$; (ii) $H₂$ $H_2$, catalyst
D. Cumene to Phenol	(IV) (i) conc. $H₂SO₄, Δ$ $H_2SO_4, \Delta$; (ii) $H^+/H₂O$ $H^+/H_2O$

Choose the correct answer from the options given below:

Chemical Reactions diagram for Q46 - JEE Main 2026 Morning — Reagent mapping for functional group conversions in organic chemistry.

A. (1) A-I, B-III, C-IV, D-II
B. (2) A-II, B-IV, C-III, D-I
C. (3) A-II, B-III, C-I, D-IV
D. (4) A-II, B-III, C-IV, D-II