Herrmann's catalyst is an organopalladium compound that is a popular catalyst for the Heck reaction.

It is a yellow air-stable solid that is soluble in organic solvents.

Under conditions for catalysis, the acetate group is lost and the Pd-C bond undergoes protonolysis, giving rise to a source of "PdP(o-tol)3".

The complex is made by reaction of tris(o-tolyl)phosphine with palladium(II) acetate:[1] Many analogues of Hermann's catalyst have been developed, e.g. palladacycles obtained from 2-aminobiphenyl.

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