Hydroxynitriles

• Molecules which contain a hydroxyl group (OH) and a nitrile group (CN)

• (For Ketones, just replace the H with an R-group).
• Prefix: Hydroxy (due to OH group)
• Suffix: Nitrile

Overall Reaction for an Aldehyde:

RCHO(aq) + KCN(aq)RCH(OH)CN(aq) + K+(aq)

Overall Reaction for a Ketone:

RCOR'(aq) + KCN(aq)RC(OH)R'CN(aq) + K+(aq)

• Double bonds such as C=O and C=C bonds are planar.
• When nucleophiles attack atoms at double bonds, they can attack from above or below the plane of the bonds.
• Nucleophilic attack from each side of the bond will produce a different enantiomer
• Nucleophilic attack of CN ion (from e.g. KCN) on aldehyes or unsymmetric ketones can lead to a racemic mixture of hydroxynitriles.
• This is because the C (delta +) by CN- can occur from either above or below the place of the C=O bond. 
• Depending on which way the nucleophile attacks from, a different enantiomer will form.
• Usually, attack from both sides is equally likely, so a racemic mixture is formed.