Question

Write the IUPAC name of methyl n-propyl ether. What is the action of hot HI on it?

Answer 1

Hint: To solve this question, we must first draw the structure and recall the rules of IUPAC nomenclature of organic compounds. We should find the longest chain of the structure first.

Complete step by step solution:
The structure of methyl n-propyl ether is as illustrated below:
$$H_{3}C-O-C{H}_2-C{H}_2-C{H}_3$$

To begin IUPAC Nomenclature we first have to
Identify the longest carbon chain and mark its carbons. This chain is called the parent chain.
We then have to identify all of the substituent groups appending from the parent chain.
The smaller, shorter alkyl group becomes the alkoxy substituent. The larger, longer alkyl group side becomes the alkane base name. Each alkyl group on each side of the oxygen is numbered separately. The numbering priority is given to the carbon closest to the oxygen.
If there are two or more different substituents, they are listed in alphabetical order using the base name.
Following this procedure this compound should be named methoxypropane.

An acid‐catalyzed cleavage that occurs when hydriodic acid (HI) mixes with ethers is the most significant reaction that ethers experience. This reaction proceeds via a nucleophilic substitution mechanism.

On adding hot HI to this, we get methyl iodide and propyl iodide along with a byproduct of water.

$$C{H}_3-O-C{H}_2-C{H}_2-C{H}_3+2HI\stackrel{hot}{\to }C{H}_{3}I+C{H}_3-C{H}_2-C{H}_2-I+H_{2}O$$

Additional information:
Methoxypropane, or methyl propyl ether, is an ether also used as a general anaesthetic. Like most others they too are clear, colourless and have low boiling point.


Note: Although ethers are relatively inert toward reaction, they have shown good solvent properties for many nonpolar organic compounds. Their strong dissolving power coupled with low reactivity makes ethers good solvents.