superbase

Superbase is a term used in chemistry to designate an exceptionally strong base. It does not refer to a single compound, but rather to a class of reagents that are significantly more basic than conventional inorganic bases and are capable of deprotonating very weak acids. In practice, superbases are often mixtures or highly reactive organometallic or amide bases that are prepared and used under strictly anhydrous, inert conditions.

Typical examples discussed in the literature include strong metal amide bases such as lithium diisopropylamide (LDA) and related diethylamide variants, as well as extremely hindered or non-nucleophilic bases and specialized mixtures like Schlosser-type bases, which combine organolithium reagents with potassium alkoxides. The exact strength and behavior of a given base depend on factors such as solvent, temperature, and the presence of counterions. Superbases are generally more prone to deprotonation than nucleophilic attack, and their high reactivity can lead to side reactions if not carefully controlled.

Applications of superbases are mainly in organic synthesis, where they enable deprotonation of substrates with high pKa values, the formation of carbanions, and the generation of enolates or other reactive intermediates that are difficult to access with ordinary bases. They are used to drive challenging C–H activation steps, directed functionalizations, and the preparation of sensitive anions for subsequent transformations. Safety and handling considerations are important due to their moisture sensitivity and potential for violent reactions with protic or oxidizing substances.

Outside of chemistry, the term has appeared as a brand or product name in software and database contexts, but such uses are unrelated to the chemical concept.