AlEt3

Aluminum triethyl, or aluminum triethyl alumin(ium) with the formula Al(C2H5)3, is a volatile organoaluminum compound. It is a highly reactive, moisture- and air-sensitive reagent that readily ignites in air and hydrolyzes violently with water, producing aluminum hydroxide and hydrocarbon byproducts such as ethane. In solution, it behaves as a strong Lewis acid and can form adducts with ethers and other donors, facilitating various alkyl transfer processes.

Properties and nomenclature: Al(C2H5)3 corresponds to a simple alkylaluminum species in which three ethyl groups are bound to aluminum. It is typically handled under inert atmosphere or in hydrocarbon solvents due to its reactivity. Its exact physical state can vary with temperature and pressure, but it is generally described as a volatile, pyrophoric liquid or condensed vapor at ambient conditions.

Applications: Triethylaluminum is widely used as a reagent in organometallic chemistry and as a co-catalyst and scavenger in olefin polymerization, particularly in TiCl4-based Ziegler–Natta systems. In catalysis, it helps generate active catalytic species by alkylating precursors and scavenging impurities such as water and oxygen, thereby improving polymerization activity and longevity. It can also transfer ethyl groups to substrates under controlled conditions in organic synthesis.

Safety and handling: Because of its pyrophoric nature, TEA is stored and used under inert gas or strictly anaerobic conditions. It reacts violently with moisture and oxygen, posing fire and explosion hazards. Spills or exposures require appropriate quenching and handling procedures by trained personnel.

See also: Organoaluminum compounds, Ziegler–Natta catalysis, alkylation reagents.