Question

Primary amines can be prepared from nitriles by reduction with LiAlH4. The two-step sequence involves SN2 displacement of halide ion by cyanide ion followed by reduction, and yields a primary amine with one more carbon than was present in the alkyl halide. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions

Answer 1

See explanation below

Step-by-step explanation:

You are not putting the mechanism step you want to be explained. I found this question, and it's attached on picture 1.

According to that, we do have a Aryl halide, reacting with cyanide ion, and then, LiAlH4.

The first step is a Sn2 reaction where the cyanide ion displace the Bromide. The second step is the reduction, which is a long step mechanism, and this is shown in pícture 2. At the end of this step, we already has added a CH2 in the molecule, and the water will allow to reduce the N group with the AlH3 to the respective primary amine.

See picture below for explanation of the mechanism