SiliaBond® Diethylamine (SiliaBond WAX-2) is a silica bound tertiary amine base and can be used in most applications requiring a tertiary amine, particularly as a HCl sponge. Silica bound ammonium salt by-products are easily separated by filtration. This diethylamine immobilized on silica gel can be used for the same applications as SiliaBond Dimethylamine. It is a very common supported tertiary amine.
SiliaBond Diethylamine is also used as weak anion exchanger (WAX) in SPE. It has a pka of ≈10.5 and is preferred over SiliaBond TMA Chloride (SAX) when performing “Catch and Release” purification of compounds bearing a permanent negative charge such as salts of sulfonic acids. Using SAX in this case could make the release of the compounds of interest difficult, not to say irreversible, due to the strong interaction between the two strong ions.