Benzylpotassium is an organopotassium compound with the formula C6H5CH2K, an orange powder.

Like organo-alkali metal reagents in general, benzyl potassium is highly reactive, so much so that it reacts with most solvents.

It is highly air sensitive.

One early synthesis proceeds by two-step transmetallation reaction by p-tolylpotassium:[1] A modern synthesis involves the reaction of butyllithium, potassium tert-butoxide, and toluene.

[2] Although potassium hydride can also be used as a strong base for preparing potassium salts, benzyl potassium has the advantage of being molecular and hence more fast-acting.