organic chemistry Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J.; ...

, propyl is a three-

carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...

alkyl In organic chemistry, an alkyl group is an alkane missing one hydrogen. The term ''alkyl'' is intentionally unspecific to include many possible substitutions. An acyclic alkyl has the general formula of . A cycloalkyl is derived from a cycloalk ...

substituent A substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. (In organic chemistry and biochemistry, the terms ''substituent'' and ''functional group'', as well as ''side ...

with

chemical formula In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, ...

for the linear form. This

form is obtained by removing one hydrogen atom attached to the terminal carbon of propane. A propyl substituent is often represented in organic chemistry with the symbol Pr (not to be confused with the element

praseodymium Praseodymium is a chemical element with the symbol Pr and the atomic number 59. It is the third member of the lanthanide series and is considered to be one of the rare-earth metals. It is a soft, silvery, malleable and ductile metal, valued for i ...

). An

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Iso ...

ic form of propyl is obtained by moving the point of attachment from a terminal carbon atom to the central carbon atom, named 1-methylethyl or isopropyl. To maintain four substituents on each carbon atom, one hydrogen atom has to be moved from the middle carbon atom to the carbon atom which served as attachment point in the ''n''-propyl variant, written as . Linear propyl is sometimes termed normal and hence written with a prefix ''n''- (i.e., ''n-''propyl), as the absence of the prefix ''n''- does not indicate which attachment point is chosen, i.e. absence of prefix does not automatically exclude the possibility of it being the branched version (i.e. ''i''-propyl or ''isopropyl''). In addition, there is a third, cyclic, form called

cyclopropyl A cyclopropyl group is a chemical structure derived from cyclopropane, and can participate in organic reactions that constitute cycloadditions and rearrangement organic reactions of cyclopropane. The group has an empirical formula of C3H5 and che ...

, or ''c''-propyl. It is not isomeric with the other two forms, having a different chemical formula ( vs ), not just a different connectivity of the atoms.

Examples

''n''-Propyl acetate is an

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides ar ...

which has the ''n''-propyl group attached to the oxygen atom of the acetate group.

Other examples

Isopropyl alcohol Isopropyl alcohol (IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a colorless, flammable organic compound with a pungent alcoholic odor. As an isopropyl group linked to a hydroxyl group ( chemical formula ) it is the s ...

References

{{Functional group Alkyl groups