The chemistry of aluminum compounds containing sterically demanding ar
yloxide ligands is presented. In particular, those of compounds derive
d from 2,6-di-tert-butyl-4-methylphenol (BHT-H, from the trivial name
butylated hydroxytoluene). The synthesis and structure of three-coordi
nate monomeric derivatives, and their ligand exchange reactions, are d
iscussed in comparison to the more typical four-coordinate oligomeric
aluminum alkoxide and aryloxide compounds. The reactions of the steric
ally crowded aryloxide compounds is divided into four general classes:
oxidation and hydrolysis, the formation of Lewis acid-base complexes,
the reaction with organic carbonyls, and the reaction with main group
halides. Alane-aryloxide compounds are discussed separately, as are t
he 1,3-diphenyltriazenide derivatives. Finally, a discussion of the Al
-O bonding interactions in four-coordinate aluminum aryloxides is pres
ented, giving spectroscopic and theoretical evidence for and against v
arious postulates to explain the presence of short Al-O distances and
large Al-O-C angles.