Correlation between the relative binding constants of amines to isolated [SPhosPd(Ph)Cl] (SPhos=2-dicyclohexylphosphino-2′,6′-dimethoxy-1,1′-biphenyl) and the pKa of the amine complexes shows that the selectivity in the catalytic arylation of amines is influenced by the electronic properties of the amine. Selectivities observed in C–N cross-coupling reactions using neutral amines can be reversed using lithium amides.
“Electronic Effects on the Selectivity of Pd-Catalyzed C–N Bond-Forming Reactions Using Biarylphosphine Ligands: The Competitive Roles of Amine Binding and Acidity”, Angew. Chem. Int. Ed., 2007, 46(38), 7232-7235.