Question
How is an aldehyde obtained from alkyl nitrile ?###What is Stephen reaction ?###Write a note on Stephen reaction.
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Answer
(1) An ethereal solution of a nitrile is reduced to imine hydrochloride by $SnCl _2$ in the presence of $HCl$ gas. Further, imine hydrochloride on acid hydrolysis gives aldehyde. This reaction is called Stephen reaction.
$Sn +2 HCl \rightarrow SnCl _2+2( H )$
(2) Alternatively, nitriles are selectively reduced by diisobi.ityl aluminium hydride (DIBAI-H) lo imines which on acid hydrolysis to aldehydes.
$Sn +2 HCl \rightarrow SnCl _2+2( H )$
(2) Alternatively, nitriles are selectively reduced by diisobi.ityl aluminium hydride (DIBAI-H) lo imines which on acid hydrolysis to aldehydes.
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