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प्रश्न
Write a note on Stephen reaction.
उत्तर
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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\[\begin{array}{cc}
\ce{O}\phantom{........}\\
||\phantom{........}\\
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\end{array}\]
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