Propan2yl

Proparan-2-yl is the alkyl substituent derived from propane by removing one hydrogen from the middle carbon, giving a secondary propyl group. The group has the formula (CH3)2CH- and attaches to a parent molecule through that central carbon, making it a secondary alkyl substituent. It is commonly referred to as the isopropyl group in non-systematic usage.

Nomenclature and synonyms: The systematic IUPAC name is propan-2-yl; other accepted names include 1-methylethyl. The term isopropyl is widely used in everyday chemistry, while propan-2-yl (or 1-methylethyl) is preferred in formal nomenclature. Spelling without hyphens (propan2yl) is seen in some contexts, but propan-2-yl is the standard IUPAC form.

Structure and properties: As a small, branched alkyl substituent, propan-2-yl is nonpolar and hydrophobic, contributing a three-carbon fragment to larger molecules. The central carbon bears two methyl groups and the attachment to the parent, and the two methyl groups are identical, so the substituent is not chiral.

Applications and examples: The propan-2-yl group appears in many compounds. Isopropylbenzene, known as cumene, contains a propan-2-yl substituent on a benzene ring. Esters such as propan-2-yl acetate and other derivatives incorporate the propan-2-yl group. Halides and alcohol-related derivatives can also feature this substituent, named accordingly as propan-2-yl halides or acylated propan-2-yl compounds.

See also: isopropyl, propan-2-yl alcohol, cumene, 1-methylethyl.