Question

When a carbohydrate reacts with $NaB{H}_4$, the product is an:

• A. Alditol
• B. Aldaric acid
• C. Aldonic acid
• D. Aglycone

Answer 1

The correct option is A Alditol

When a carbohydrate reacts with $NaB{H}_4$, the product is an alditol.
The $C=O$ groups in open chain forms of carbohydrates can be reduced to alcohols by sodium borohydride, $NaB{H}_4$, or catalytic hydrogenation ($H_2$, Ni, EtOH/$H_{2}O$). Aldehydes, i.e. aldoses, are reduced to primary alcohols. Ketones, i.e. ketoses, are reduced to secondary alcohols.