Reactions of crotyl alcohol with reagents Steps:

• Structure: CH3CH=CHCH2OH (primary allylic alcohol; given formula likely omits CH2).
• Br2 adds to alkene via electrophilic addition, yielding CH3CHBrCHBrCH2OH.
• K2Cr2O7/H+ oxidizes primary alcohol to carboxylic acid under reflux, yielding CH3CH=CHCOOH.
• Conc. KMnO4 oxidatively cleaves alkene under reflux, yielding CH3COOH + HOCH2COOH.
• PCl3 substitutes OH with Cl via SN2, yielding CH3CH=CHCH2Cl (saturated formula approximates chain).

Why D is correct:

• PCl3 converts ROH to RCl per 3ROH + PCl3 → 3RCl + H3PO3, targeting alcohol group without altering double bond.

Why the others are wrong:

• A: Addition retains OH, gives vicinal dibromide CH3CHBrCHBrCH2OH, not CH3CHBrCH2Br.
• B: Reflux conditions oxidize to acid CH3CH=CHCOOH, not saturated aldehyde.
• C: Cleavage breaks C=C, gives two acids, not single CH3CH2COOH.

Final answer: D