C4H9I

C4H9I is the chemical formula for several isomers of iodobutane. These are organic compounds belonging to the class of alkyl halides. The molecular formula indicates a molecule composed of four carbon atoms, nine hydrogen atoms, and one iodine atom. Due to the arrangement of the carbon chain, there are four distinct structural isomers of iodobutane: 1-iodobutane, 2-iodobutane, isobutyl iodide (or 1-iodo-2-methylpropane), and tert-butyl iodide (or 2-iodo-2-methylpropane).

1-iodobutane and 2-iodobutane are straight-chain isomers, differing in the position of the iodine atom. Isobutyl iodide features a branched carbon chain with the iodine attached to a primary carbon atom at the end of the chain. Tert-butyl iodide has a tertiary carbon atom bonded to the iodine atom, making it the most sterically hindered of the isomers.

These compounds are typically synthesized through reactions involving alcohols and iodine-containing reagents. They can undergo various chemical transformations, including nucleophilic substitution and elimination reactions, characteristic of alkyl halides. Their physical properties, such as boiling point and density, vary among the isomers due to differences in molecular structure and intermolecular forces. Iodobutanes can be used as intermediates in organic synthesis for the introduction of a butyl group or for the formation of other functional groups through substitution of the iodine atom.