Reductive amination consists of forming an imine, from aldehydes or ketones and amines, which is reduced to an amine in a subsequent stage. This reduction can be carried out with H 2 catalyzed by Nickel or with NaBH 3 CN.

 
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The reaction proceeds with formation of imine from propanal and ammonia.
 
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The imine double bond is reduced with H 2 , Ni, to form the final amine.
 
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Let's see a second example
 
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In the first stage, the imine is formed from cyclohexanone and methylamine.
 
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In the second stage, sodium cyanoborohydride reduces the imine to an amine.
 
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