Metal-ligand bonds in coordination compounds

Cr-Cr Quintuple Bonds: Ligand Topology and Interplay Between Metal-Metal and Metal-Ligand Bonding.

Chromium-chromium quintuple bonds seem to be approaching the lower limit for their bond distances, and this computational density functional theory study tries to explore the geometrical and electronic factors that determine that distance and to find ways to fine-tune it via the ligand choice. While for monodentate ligands the Cr-Cr distance is predicted to shorten as the Cr-Cr-L bond angle inc...

Photochemistry of Transition Metal Coordination Compounds

METAL-LIGAND MULTIPLE BONDS IN ORGANOMETALLIC COMPLEXES CONTAINING TRIAMIDOAMINE LIGAND SYSTEMS by JOEL

Chapter 1 The synthesis and reactivity of [N3N]Ta=E complexes is presented where E is a la, l or la, 21t donor and [N3N] 3= [(Me3SiNCH 2CH2)3N]. [N3N]Ta=PPh reacts with excess lithium metal in tetrahydrofuran to give "[N3N]Ta=PLi" which reacts with RX at -35 'C to afford the phosphinidene complexes, [N3N]Ta=PR (R = Me, n-Bu, SiMe3 , SiMe2Ph). [N3N]TaCl 2 reacts with two equivalents of LiN(H)R (...

Metal-coordination-driven mixed ligand binding in supramolecular bisporphyrin tweezers.

Mg(II)bisporphyrin has been used as an efficient host for the selective binding of guest ligands. In the presence of heterogeneous guest pairs, 2-aminopyrimidine/pyrazine and 2-aminopyrimidine/1,4-dioxane, 2-aminopyrimidine is bound selectively inside the bisporphyrin cavity whereas pyrazine/1,4-dioxane is bound outside to produce 1D mixed ligand polymers. UV-vis, (1)H NMR spectra and X-ray str...

The usefulness of EPR spectroscopy in the study of compounds with metal-metal multiple bonds.

This Perspective reviews some of the contributions that EPR spectroscopy has made for the understanding of the bonding and electronic structure of molecular species with metal-to-metal multiple bonds. The goal is to show how useful this technique can be in (a) elucidating whether unpaired electrons reside in metal-based or ligand-based molecular orbitals, (b) providing information on the metal ...