HAFNIUM TETRACHLORIDE Hafnium(IV) chloride, 99%

Hafnium(IV) chloride is the inorganic compound with the formula HfCl₄. This colourless solid is the precursor to most hafnium organometallic compounds. 

Chemical formula:HfCl₄

Molar mass:320.302 g/mol

Appearance:white crystalline solid

Density:3.89 g/cm³

Melting point:432 °C (810 °F; 705 K)

Application

Hafnium tetrachloride is the precursor to highly active catalysts for the Ziegler-Natta polymerization of alkenes, especially propylene. Typical catalysts are derived from tetrabenzylhafnium.

HfCl₄ is an effective Lewis acid for various applications in organic synthesis. For example, ferrocene is alkylated with allyldimethylchlorosilane more efficiently using hafnium chloride relative to aluminium trichloride. The greater size of Hf may diminish HfCl₄'s tendency to complex to ferrocene.

HfCl₄ increases the rate and control of 1,3-dipolar cycloadditions. It was found to yield better results than other Lewis acids when used with aryl and aliphatic aldoximes, allowing specific exo-isomer formation.