Question

What is the systematic name of the compound `CH_3CH(OH)CH_2CHO`?

Answer 1

The systematic name is 3-hydroxybutanal.

Explanation:

Step 1. Draw the longest continuous chain of carbon atoms

`"C-C-C-C"`

There are four carbon atoms, so the base name is butane.

Step 2. Identify the functional group of highest priority

`"C-C-C-CHO"`

The group with highest priority is the aldehyde group.

We drop the "-e" fron "butane" and add the suffix "-al".

The name becomes butanal.

Step 3. Identify the other functional group.

`"C-C(OH)-C-CHO"`

The `"OH"` group is a hydroxyl group.

The name becomes hydroxybutanal.

Step 4. Number the atoms in the main chain and locate the hydroxyl group

The aldehyde carbon is number 1.

`stackrelcolor(blue)(4)("C")"-"stackrelcolor(blue)(3)("C")"(OH)-"stackrelcolor(blue)(2)("C")"-"stackrelcolor(blue)(1)("C")"HO"`

The hydroxyl group is on carbon 3, so the name of

`"CH"_3"CH(OH)CH"_2"CHO"`

is 3-hydroxybutanal,