Herrmann's catalyst explained

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 "".

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.^[2]

Notes and References

1. Herrmann, W. A.. Brossmer, C.. Reisinger, C.-P.. Riermeier, T. H.. Öfele, K.. Beller, M.. Palladacycles: Efficient New Catalysts for the Heck Vinylation of Aryl Halides. Chemistry – A European Journal. 1997. 3. 1357–1364. 10.1002/chem.19970030823.
2. Bruneau, A.. Roche, M.. Alami, M.. Messaoudi, S.. 2-Aminobiphenyl Palladacycles: The "Most Powerful" Precatalysts in C–C and C–Heteroatom Cross-Couplings. ACS Catalysis. 2015. 5. 1386–1396. 10.1021/cs502011x.