Triethylborane

Triethylborane (CAS 97-94-9), also known as TEB, Borethyl, or boron ethyl, is an organoboron compound with the formula (C2H5)3B. It carries no assigned E-code and is classified under HS code 29319090. It is commercially available as a clear colourless to light amber liquid solution.

In polyolefin production, TEB acts as a co-catalyst alongside Ziegler-Natta systems, activating transition metal centres to initiate controlled chain growth. It is also used in pharmaceutical synthesis as a radical initiator, generating ethyl radicals at low temperatures to drive selective carbon-carbon bond-forming reactions in complex molecule construction.

TEB is supplied in stabilised solution grades formulated for handling safety, given its pyrophoric nature. It is subject to REACH registration requirements within the EU and must be handled under inert atmosphere conditions. Packaging is typically provided in specialised sealed containers appropriate for air-sensitive materials.