Borane-triethylamine complex

Borane-triethylamine complex (CAS 1722-26-5, EC 217-022-3) is a stabilised borane reagent commercially known as TEAB or triethylamine borane, with the abbreviated formula (C2H5)3NBH3. It carries no assigned E-code. The triethylamine ligand moderates the reactivity of the borane, making it safer to handle than free borane gas.

In pharmaceutical synthesis, TEAB functions as a selective reducing agent for imines and carbonyl compounds under controlled conditions, offering chemists a milder alternative to lithium aluminium hydride. In polymer chemistry, it serves as a radical initiator for polymerisation reactions, generating boron-centred radicals that activate monomer chains at ambient or low temperatures.

TEAB is supplied under REACH compliance and is available in standard laboratory and bulk quantities as a neat liquid. Procurement teams should confirm purity grade and inhibitor content with the supplier prior to ordering, as specifications vary by intended application.