Dioxygen activation by a low-valent cobalt complex employing a flexible tripodal N-heterocyclic carbene ligand.
The novel versatile cobalt(I) tris-carbene complex [(TIMEN(xyl))Co]Cl (1) (where TIMEN = (tris[2-(3-arylimidazol-2-ylidene)ethyl]amine) reacts with CO, one-electron oxidizers such as CH(2)Cl(2), and O(2) to yield the cobalt complexes [(TIMEN(xyl))Co(CO)]Cl (2), [(TIMEN(xyl))Co(Cl)]Cl (3), and peroxo species [(TIMEN(xyl))Co(O(2))](BPh(4)) (5). All new complexes were fully characterized by (1)H NMR, UV/vis, and IR spectroscopy as well as superconducting quantum interference device (SQUID) magnetization measurements and single-crystal X-ray crystallography. The nucleophilic character of the eta(2)-bound dioxygen ligand in 5 was confirmed by density functional theory (DFT) studies and allows for oxygen-transfer reactions with electron-deficient organic substrates, such as benzoyl chloride.
Department of Chemistry and Biochemistry, Mail Code 0358, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0358, USA.
Xile
X
Hu
Ingrid
I
Castro-Rodriguez
Karsten
K
Meyer
D003035:Cobalt / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D006838:Hydrocarbons; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D010720:Phosphines / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet
D006571:Heterocyclic Compounds; D006838:Hydrocarbons; D008024:Ligands; D009942:Organometallic Compounds; D010720:Phosphines; C030011:carbene; D003035:Cobalt; D008697:Methane; D010100:Oxygen