Herrmann's catalyst

Herrmann's catalyst
Identifiers
CAS Number	172418-32-5;
3D model (JSmol)	Interactive image;
ChemSpider	10136140;
EC Number	681-425-4;
PubChem CID	15978061;
UNII	0K4FY6KS4N;
CompTox Dashboard (EPA)	DTXSID40704833 ;
	InChI InChI=1S/2C21H20P.2C2H4O2.2Pd/c21-16-10-4-7-13-19(16)22(20-14-8-5-11-17(20)2)21-15-9-6-12-18(21)3;21-2(3)4;;/h24-15H,1H2,2-3H3;21H3,(H,3,4);;/q2-1;;;2+2/p-2 Key: AQTSNKXEMWZOGA-UHFFFAOYSA-L;
	SMILES CC1=CC=CC=C1P(C2=CC=CC=C2C)C3=CC=CC=C3[CH2-].CC1=CC=CC=C1P(C2=CC=CC=C2C)C3=CC=CC=C3[CH2-].CC(=O)[O-].CC(=O)[O-].[Pd+2].[Pd+2];
Properties
Chemical formula	C46H46O4P2Pd2
Molar mass	937.66 g·mol−1
Appearance	Yellow solid
Melting point	123–125 °C (253–257 °F; 396–398 K)
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Precautionary statements	P261, P264, P264+P265, P271, P280, P302+P352, P304+P340, P305+P351+P338, P319, P321, P332+P317, P337+P317, P362+P364, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

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".

Preparation

2 Pd(OAc)₂ + 2 P(o−tolyl)₃ → 2 HOAc + Pd₂(OAc)₂[P(o−tolyl)(o−tolyl)₂]₂

Many analogues of Hermann's catalyst have been developed, e.g. palladacycles obtained from 2-aminobiphenyl.^[3]

↑ PubChem. "Herrmann'S catalyst". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-02-27.
↑ Herrmann, W. A.; Brossmer, C.; Reisinger, C.-P.; Riermeier, T. H.; Öfele, K.; Beller, M. (1997). "Palladacycles: Efficient New Catalysts for the Heck Vinylation of Aryl Halides". Chemistry – A European Journal. 3 (8): 1357–1364. Bibcode:1997ChEuJ...3.1357H. doi:10.1002/chem.19970030823.
↑ Bruneau, A.; Roche, M.; Alami, M.; Messaoudi, S. (2015). "2-Aminobiphenyl Palladacycles: The "Most Powerful" Precatalysts in C–C and C–Heteroatom Cross-Couplings". ACS Catalysis. 5 (2): 1386–1396. doi:10.1021/cs502011x.