Question

How do you name ethers, esters, and nitriles? Which IUPAC naming method is right?

Answer 1

Here's what I get.

Explanation:

When there is more than one permissible IUPAC name, the first name is preferred.

Ethers

There are two systems of IUPAC names for ethers.

1. Substitutive names.

The ethers are named as alkoxyalkanes, with the senior component selected as the parent compound.

Thus, `"CH"_3"OCH"_2"CH"_2"CH"_3` is 1-methoxypropane.

2. Functional group names.

The ethers are named as alkyl alkyl ethers, with the alkyl groups in alphabetical order followed by the class name ether, each as a separate word.

Thus, `"CH"_3"OCH"_2"CH"_2"CH"_3` is methyl propyl ether.

Esters

Esters are named as alkyl alkanoates.

The name of the alkyl group is written first, followed by the name of the acid with the ending -ic acid replaced by the ending -ate.

Thus, `"CH"_3"CH"_2"COO-CH"_3` is methyl propanoate (two words).

Cyanides (nitriles)

There are three systems of IUPAC names for nitriles.

1. As alkanenitriles.

The ending -nitrile is added to the name of the alkane with the same number of carbon atoms.

Thus, `"CH"_3"CH"_2"C≡N"` is propanenitrile.

2. If the compound is considered to be formed from a carboxylic acid with a "trivial name" (`"RCOOH → RC≡N"`), the ending -ic acid is changed to -onitrile.

Thus, `"CH"_3"CH"_2"C≡N"` is also called propionitrile (from propionic acid).

3. As alkyl cyanides.

The name of the alkyl group precedes the class name cyanide.

Thus, `"CH"_3"CH"_2"-C≡N"` is ethyl cyanide (two words).