4methyl
4-methyl is a locant used in chemical nomenclature to indicate a methyl substituent attached to the fourth carbon of a parent molecule. It is employed in systematic IUPAC names for a wide range of compounds, including monocyclic rings such as 4-methylcyclohexane and benzene derivatives. The 4-position designation specifies the position of the methyl group on the ring or chain, and it helps distinguish isomers that differ only by where the methyl group is attached.
In the context of benzene rings with multiple substituents, the 4-position is para to a reference substituent
Examples include 4-methylcyclohexane, where a methyl group occupies the fourth carbon of a cyclohexane ring; 4-methylbenzaldehyde