Question

In the following reaction, identify A and B:

\[\begin{array}{cc}
\ce{C6H12O6 ->[Acetic anhydride] A}\\
\downarrow \text{Conc. nitric acid}\phantom{...}\\
\ce{B}\phantom{.................}\end{array}\]

Options

• A = \[\ce{COOH-(CH2)4 -COOH}\], B = \[\ce{OHC-(CHOCOCH3)4 -CH2OCOCH3}\]

• A = \[\ce{COOH-(CH2)4 -CHO}\], B = \[\ce{OHC-(CHOCOCH3)4 -CH2OCOCH3}\]

• A = \[\ce{OHC-(CHOCOCH3)3-CH2OCOCH3}\], B = \[\ce{COOH-(CH2)4 -CHO}\]

• A = \[\ce{OHC-(CHOCOCH3)4-CH2OCOCH3}\] B = \[\ce{COOH-(CH2)4 -COOH}\]

Answer 1

A = \[\ce{OHC-(CHOCOCH3)4-CH2OCOCH3}\] B = \[\ce{COOH-(CH2)4 -COOH}\]

Explanation:

\[\begin{array}{cc}
\ce{CHO}\phantom{.............................}\ce{CHO}\phantom{........................}\\
|\phantom{.................................}|\phantom{...........................}\\
\ce{(CHOH4) + \underset{Acetic anhydride}{5(CH3CH)2O}-> (CHOCOCH3)4 + 5CH3COOH}\\
\phantom{....}|\phantom{..............................}|\phantom{........}\ce{O}\phantom{.....................}\\
\phantom{.....................}||\\
\ce{\underset{\text{glucose}}{CH2OH}}\phantom{......................}\ce{\underset{\text{Glucose penta acetate}}{CH2O - C - CH3}}\phantom{.......}
\end{array}\]