Question

Solve the following reaction:
\[{C_2}{H_5}OH{\text{ }}\xrightarrow{{Na}}{\text{ A }}\xrightarrow{{{C_2}{H_5}Br}}{\text{ B}}\]

Answer 1

Hint: When alcohol is made to react with a metal like sodium then it forms an ionic bond with the metal ion. This is due to the replacement of hydrogen atoms by sodium metal atoms. Further when this ionic compound is made to react with organic compounds like ethyl bromide then an ether is formed.

Complete answer:
Ethyl alcohol is an organic compound which is made to react with sodium metal. Due to the presence of hydroxyl groups, a polarity is developed in the hydroxyl group due to the difference of electronegativity between hydrogen and oxygen atoms. Thus when sodium metal is made to react with alcohols then hydrogen atom is replace by sodium metal and thus formed a complex as,
\[{C_2}{H_5}{O^ - } - {H^ + }{\text{ }}\xrightarrow{{Na}}{\text{ }}{C_2}{H_5}{O^ - } - N{a^ + }\]
Further when this complex is made to react with ethyl bromide then anion part of ethyl bromide combines with sodium ion and we get the diethyl ether as our main product. We get sodium bromide as our by-product in the reaction. This can be shown as,
\[{C_2}{H_5}{O^ - } - N{a^ + }{\text{ }}\xrightarrow{{{C_2}{H_5} - B{r^ - }}}{\text{ }}{C_2}{H_5} - O - {C_2}{H_5}{\text{ + NaBr}}\]
Thus we get the final main product as di-ethyl ether. This reaction is also known as the William synthesis reaction. It is used for preparation of ether commercially. The by-product is sodium bromide which is ionic in nature.

Note:
We will prefer to use sodium metal because its reactivity is higher than other metal atoms. Also it is a monovalent atom which makes a single bond. The process which involved above is used for making ether at large scale. It is an economical method for production of ether.