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Reduction of an unsaturated aldehyde: LiAlH4 versus H2/Ni

This type of question, asked 2 times: 9 May 2023 S1, 16 Apr 2026 S1. All 2 questions below, oldest first.

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  1. Question 1

    9 May 2023 S1

    94
    What is the product obtained in the reaction? CH3-CH=CH-CH2-CHO→(i) LiAlH4, (ii) H3O+\text{CH}_3\text{-CH=CH-CH}_2\text{-CHO} \xrightarrow{(i)\,\text{LiAlH}_4,\,(ii)\,\text{H}_3\text{O}^+} product

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  2. Question 2

    16 Apr 2026 S1

    42
    An organic compound CH3-CH=CH-CH2-CHO\mathrm{CH_3\text{-}CH{=}CH\text{-}CH_2\text{-}CHO} is taken in two different containers A and B. Sample in A is treated with H2\mathrm{H_2} / Ni forming new compound P. Sample in B is treated with LiAlH4\mathrm{LiAlH_4} and hydrolyzed further forming new compound Q. Identify P and Q.

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