Monodentate phosphine substitution in [Pd(κ 3 -dppf)(PR 3 )][BF 4 ] 2 (dppf = 1,1'-bis(diphenylphosphino)ferrocene) compounds

• Published in: Dalton transactions : an international journal of inorganic chemistry 2017, Vol.46 (17), p.5702-5710
• Main Authors: Cabrera, K D, Rowland, A T, Szarko, J M, Diaconescu, P L, Bezpalko, M W, Kassel, W S, Nataro, C
• Format: Article
• Language: English
• Subjects: Associative; Catalysis; Crystal structure; Iron; Ligands; Phosphines; Synthesis; X rays
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c6dt04921d

The ligand 1,1'-bis(diphenylphosphino)ferrocene (dppf) is commonly employed in a variety of catalytic systems. There are a variety of coordination modes known for dppf, the least studied being the κ coordination mode, in which both phosphorus atoms and the iron atom of dppf interact with another metal center. One such compound is the previously reported [Pd(κ -dppf)(PPh )] . A series of related compounds, [Pd(κ -dppf)(P(p-C H R) )] (R = OCH , CH , F and CF ), has been synthesized and characterized. The X-ray crystal structure of [Pd(dppf)(P(p-C H F) )][BF ] was determined. Electrochemical and computational studies indicate that the electron donor ability of the P(p-C H R) ligands influences the properties of these compounds. Substitution reactions of the P(p-C H R) ligands have been examined, and, in general, the more electron donating P(p-C H R) ligands completely replace the less electron donating ones. The kinetics of the reaction of [Pd(κ -dppf)(P(p-C H F) )] with P(p-C H OCH ) indicate that the reaction proceeds through a dissociative mechanism, contrary to the associative substitutions prevalent in square planar palladium(ii) chemistry.