Question

Write the reactions of glucose with
(a) HI
(b)\((CH_3CO_2)O\)

Hint:

Glucose can undergo reduction and acetylation reactions. Reduction with HI removes oxygen functionality, yielding \( n \)-hexane. Acetic anhydride reacts with all hydroxyl (-OH) groups, forming pentaacetate derivatives.

Answer 1

Step 1: Glucose reduction with HI Heating glucose with hydroiodic acid (HI) completely reduces it, removing all oxygen functionalities to yield \( n \)-hexane. The equation is: \[ \text{CHO} - (\text{CHOH})_4 - \text{CH}_2\text{OH} \xrightarrow{\text{HI}, \Delta} \text{CH}_3 - \text{CH}_2 - \text{CH}_2 - \text{CH}_2 - \text{CH}_3 \] Step 2: Acetylation of glucose with Acetic Anhydride Treatment of glucose with acetic anhydride \((CH_3CO)_2O\) results in the acetylation of all hydroxyl groups, forming glucose pentaacetate. The reaction is depicted below: