| Late transition metal complexes are traditionally employed as catalysts for a variety of organic transformations. The hydrosilylation reaction represents the formal addition of a Si-H bond to an unsaturated organic substrate, and is one such transformation that has received much attention in the scientific literature. The recent development of a series of P,N- and P-substituted indene ligands by the Stradiotto group prompted a study of group 10 and 11 complexes derived from these complexes. Synthesis and structural characterization of Pd(II), Pt(II), Au(III) and Au(I) species is reported, followed by stability and reactivity studies for these complexes. Selected complexes, as well as several M(I)/phosphine (M = Ag, Au) mixtures were evaluated as catalysts for the hydrosilylation reaction. Comparison of a neutral Pt(II) complex and a closely related neutral, charge-separated Au(III) zwitterion reveals significant differences in stability and reactivity, as well as in catalytic competence for the hydrosilylation of alkenes. Key Pt(II) complexes also display interesting reactivity that points to the potential for related species to accomplish intermolecular C-H bond activation. The Ag(I) and Au(I) catalyst systems described represent the first examples of Ag-mediated and room temperature Au-mediated hydrosilylation reactions, and as such, represent a significant contribution to scientific development. Future directions and proposed modifications to substituted indene ligands are discussed. |
