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Write a note on Stephen reaction.

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Question

Write a note on Stephen reaction.

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Solution

Nitriles are reduced to imine hydrochloride by stannous chloride in presence of hydrochloric acid which on acid hydrolysis give corresponding aldehydes. This reaction is called Stephen reaction.

\[\ce{\underset{(Alkane nitrile)}{R - C ≡ N +}2[H] ->[SnCl2, HCl]\underset{(Imine hydrochloride)}{R - HC = NH.HCl}->[H3O+]\underset{(Aldehyde)}{R - CHO} + NH4Cl}\]

e.g. \[\ce{\underset{(Ethanenitrile)}{H3C - C ≡ N}+2[H] ->[SnCl2, HCl][(reduction)]\underset{(Ethanimine hydrochloride)}{CH3 - HC = NH.HCl}->[H3O+]\underset{(Ethanal)}{CH3 - CHO} + NH4Cl}\]

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Chapter 12: Aldehydes, Ketones and Carboxylic acids - Exercises [Page 281]

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Balbharati Chemistry [English] Standard 12 Maharashtra State Board
Chapter 12 Aldehydes, Ketones and Carboxylic acids
Exercises | Q 4.1 | Page 281

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