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JEE Main levelOne or more correct optionsDifficulty 2 of 3ro233

The compound shown is reduced with hydride or hydrogenation reagents. Select ALL correct statements.

  1. A in ethanol gives the allylic alcohol, with the C=C bond left intact.
  2. BThe product retains the E geometry of the double bond.
  3. C (excess) over Pd/C at room temperature and 1 atm reduces both the C=C and the C=O group, giving the saturated primary alcohol with the benzene ring intact.
  4. D also reduces the benzene ring.

Answer: A, B, C

The compound is (E)-cinnamaldehyde. reduces the aldehyde (1,2-reduction) to (E)-cinnamyl alcohol without touching the conjugated alkene or the ring (statements 1 and 2 true). Catalytic hydrogenation over Pd/C at room temperature and 1 atm reduces both C=C and C=O but not the aromatic ring, giving 3-phenylpropan-1-ol (true). Hydride reagents never reduce the benzene ring (statement 4 false).
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