1Iodobutane

1-Iodobutane, also known as n-butyl iodide, is an organohalogen compound with the chemical formula C4H9I. It is a primary alkyl halide where an iodine atom is bonded to a terminal carbon of a four-carbon chain. This compound is a colorless liquid at room temperature and pressure. It has a molecular weight of 198.01 g/mol.

1-Iodobutane is typically synthesized through the reaction of 1-butanol with an iodinating agent, such as phosphorus triiodide or a mixture of iodine and red phosphorus. It can also be prepared via the Finkelstein reaction, where 1-chlorobutane or 1-bromobutane is treated with sodium iodide in a polar aprotic solvent like acetone.

In organic chemistry, 1-iodobutane serves as a useful reagent for introducing the butyl group into other molecules. Its primary use is as an alkylating agent in nucleophilic substitution reactions. The carbon-iodine bond is relatively weak and polarized, making the iodine atom a good leaving group, facilitating reactions with various nucleophiles like alkoxides, amines, and carbanions. It is often employed in the synthesis of ethers, amines, and Grignard reagents. Due to its relatively higher reactivity compared to its chloro- or bromo- counterparts, it is favored in certain synthetic pathways requiring milder conditions or faster reaction rates. It is important to note that alkyl iodides can be sensitive to light and should be stored appropriately.