Examples include the addition of sodium bisulfite to an aldehyde to give a sulfonate.
[3] Trimethylborane, trimethyltin chloride and bis(hexafluoroacetylacetonato)copper(II) are examples of Lewis acids that form adducts which exhibit steric effects.
Compounds or mixtures that cannot form an adduct because of steric hindrance are called frustrated Lewis pairs.
A good example from solid-state chemistry is the adducts of ethylene or carbon monoxide of CuAlCl4.
Upon formation of the adduct, a new extended phase is formed in which the gas molecules are incorporated (inserted) as ligands of the copper atoms within the structure.