Development of metal-ligand cooperation in bis(phosphinimine)pyrrolide complexes of rhodium
University of Lethbridge. Faculty of Arts and Science
Lethbridge, Alta. : University of Lethbridge, Dept. of Chemistry & Biochemistry
The synthesis and characterization of bis(phosphinimine)pyrrolide complexes of rhodium is described. A combination of solution and solid-state spectroscopies, X-ray crystallography, and computational analyses were used to characterize relevant compounds. Crystallographic analysis of phosphinimine fragments in the reported rhodium complexes showed significant P–N bond elongation relative to uncoordinated phosphinimines in both the parent ligand scaffold and partially-coordinated (κ2-N,N) species, emphasizing the ylidic structure of the P–N linkage. In the rhodium complexes surveyed, hemilabile phosphinimines were shown to engage small molecule substrates leading to heterolytic cleavage of H2, CO deoxygenation, dehydrogenation of hydrosilanes, and the reversible activation of B–H bonds. Catalytic hydrogenation of alkenes and alkynes could be initiated from well-defined mononuclear complexes of the bis(phosphinimine)pyrrolido ligand. Taken together, the incorporation of phosphinimines in a monoanionic ligand scaffold paired with rhodium enabled new reactivities, representing an advancement in metal-ligand cooperation.
Chemistry , Analytical chemistry , Dissertations, Academic , Metallurgical analysis , Rhodium , Spectrophotometry , X-ray crystallography