New palladium based catalysts from Johnson Matthey

Johnson Matthey (JM) has expanded its field of interest in the pharmaceutical industry. At the CPhI show JM was highlighting a number of new catalysts including third generation products such as a palladium (I) dimer, Pd(PCy₃)₂Cl₂, and triaryl phosphite based palladacycle compounds.

The palladium (I) compound,¹ palladium (I) tri-tert-butylphosphine bromide dimer, [Pd(P^tBu3)(µ-Br)]₂, is a highly active catalyst for coupling reactions and will activate aryl chlorides and sterically hindered or electron rich aryl bromides.² It is especially active in difficult aminations and heteroaryl halide couplings, has very fast turnover rates³ and is easy to handle.

The triaryl phosphite based palladacycle is now available on a commercial scale, having been used previously in academia only.

The catalyst contains the tris(2,4-di-tert-butylphenyl)phosphite ligand. It shows very high activity and turnover rates, with catalyst loadings of 10⁴ mol% used for certain reactions.^4,5