Question

I find it hard to remember which is vinylic and allylic carbon, so I feel it would be easier to remember if I know the reason why they are named so, like their word root origin or something like that. What is the historic origin of the term vinylic and allylic?

Answer 1

The term 'vinylic' originates from 'vinum', Latin for wine, related to the association with ethanol in wine, while the term 'allylic' comes from 'allium', meaning garlic, due to allyl compounds being first obtained from garlic oil. Vinylic carbons are part of a double bond, and allylic carbons are adjacent to a double bond.

Step-by-step explanation:

The terms vinylic and allylic refer to specific types of carbon atoms in organic chemistry. A vinylic carbon is one that is directly attached to a double bond, as seen in vinyl groups (C=C).

The term 'vinyl' comes from the Latin 'vinum' for wine, because ethenyl, the simplest vinyl compound, was historically associated with the production of ethanol in wine.

On the other hand, an allylic carbon is the next carbon atom adjacent to a double bond. The name 'allyl' is derived from the Latin word 'allium', meaning garlic, as allyl compounds were first isolated from the oil of garlic.

Understanding the historical etymology of these terms might help students remember which is which: vinylic carbon atoms participate directly in a double bond, whereas allylic carbon atoms are adjacent to that double bond.