Question

Acetic anhydride + diethyl ether in the presence of anhydrous $AlC{{l}_{3}}$ gives product:
(A).$C{{H}_{3}}COOC{{H}_{3}}$
(B).$C{{H}_{3}}C{{H}_{2}}COOC{{H}_{3}}$
(C).$C{{H}_{3}}COO{{C}_{2}}{{H}_{5}}$
(D).$C{{H}_{3}}C{{H}_{2}}COO{{H}_{{}}}$

Answer 1

Hint: The term anhydrous is used for substances that do not contain water. In the case of crystalline compounds, when the water of crystallization is removed the compound left is anhydrous compounds.

Complete answer:
Acetic anhydride reacts with diethyl ether in the presence of anhydrous $AlC{{l}_{3}}$to give ethyl acetate. 

> The reaction involves is shown below:
\[{{(C{{H}_{3}}CO)}_{2}}O+({{C}_{2}}{{H}_{5}})O\xrightarrow{AlC{{l}_{3}}}2C{{H}_{3}}COO{{C}_{2}}{{H}_{5}}\]
> In this reaction anhydrous $AlC{{l}_{3}}$acts as a Lewis acid and the reactants rearrange themselves to produce two moles of ethyl acetate.

Hence the correct answer is option C.

Additional information:
> Ethyl acetate is a colorless liquid which is also known as ethyl ethanoate. The chemical formula of ethyl acetate is $C{{H}_{3}}COO{{C}_{2}}{{H}_{5}}$. Ethyl acetate is a polar aprotic solvent and it is also used as a standard solvent. Ethyl acetate is a very important chemical compound.
> Ethyl acetate is used in paints, lacquers, varnishes, cleaning and also in perfumes. The process of thermal decomposition of ethyl acetate is a first order unimolecular reaction. The kinetic and the thermodynamic parameters are obtained by using the Arrhenius equation. The temperature in the process of thermal decomposition of ethyl acetate ranges from 400 to 600$^{0}C$.
> Pyrolysis of ethyl acetate gives ethane and acetic acid as major products. This reaction is a syn- elimination. There is formation of transition state during this reaction.

Note: The anhydrous aluminium chloride is a strong Lewis acid. It is used to promote the chlorination of the aromatic compounds and it is also used in reactions like Friedel-Craft acylation.