Write the reaction when D-glucose reacts with acetic anhydride.
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Solution and Explanation
All five hydroxyl groups are acetylated. The product is glucose pentaacetate, which has no free \(-\mathrm{OH}\) group left. This shows that glucose has five hydroxyl groups.
\[ \mathrm{CH_2OH(CHOH)_4CHO + 5(CH_3CO)_2O \to CH_3COOCH_2(CHOCOCH_3)_4CHO + 5CH_3COOH} \]
Final Answer:
D-glucose reacts with acetic anhydride to give glucose pentaacetate.
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