Propyl

In organic chemistry, propyl is a three-carbon alkyl substituent with chemical formula -C₃H₇. It is the substituent form of the alkane propane.

For example:

This is "propyl ethanoate," an ester. The propyl group is attached to the molecule after the middle oxygen.

There are two isomeric forms of propyl:

with the substituent attached to one of the end carbons (called 1-propyl in the IUPAC nomenclature, or n-propyl in the old naming system); and
with the substituent attached to the middle carbon (called 2-propyl in the IUPAC system, or isopropyl in the old system).

In addition there is a third, cyclic, form called cyclopropyl, or c-propyl.