Synthesis and reactivity of a mononuclear non-haem cobalt(IV)-oxo complex.
Terminal cobalt(IV)-oxo (CoIV-O) species have been implicated as key intermediates in various cobalt-mediated oxidation reactions. Herein we report the photocatalytic generation of a mononuclear non-haem [(13-TMC)CoIV(O)]2+(2) by irradiating [CoII(13-TMC)(CF3SO3)]+(1) in the presence of [RuII(bpy)3]2+, Na2S2O8, and water as an oxygen source. The intermediate 2 was also obtained by reacting 1 with an artificial oxidant (that is, iodosylbenzene) and characterized by various spectroscopic techniques. In particular, the resonance Raman spectrum of 2 reveals a diatomic Co-O vibration band at 770 cm-1, which provides the conclusive evidence for the presence of a terminal Co-O bond. In reactivity studies, 2 was shown to be a competent oxidant in an intermetal oxygen atom transfer, C-H bond activation and olefin epoxidation reactions. The present results lend strong credence to the intermediacy of CoIV-O species in cobalt-catalysed oxidation of organic substrates as well as in the catalytic oxidation of water that evolves molecular oxygen.
Department of Chemistry and Nano Science, Center for Biomimetic Systems, Ewha Womans University, Seoul 03760, Korea.
Bin
B
Wang
Department of Chemistry and Nano Science, Center for Biomimetic Systems, Ewha Womans University, Seoul 03760, Korea.
Yong-Min
YM
Lee
Department of Chemistry and Nano Science, Center for Biomimetic Systems, Ewha Womans University, Seoul 03760, Korea.
Woon-Young
WY
Tcho
Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea.|Department of Chemistry, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea.
Samat
S
Tussupbayev
Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea.|Department of Chemistry, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea.
Seoung-Tae
0000-0003-4067-9567
ST
Kim
Western Seoul Center, Korea Basic Science Institute, Seoul 03759, Korea.
Yujeong
Y
Kim
Department of Chemistry and Nano Science, Center for Biomimetic Systems, Ewha Womans University, Seoul 03760, Korea.
Mi Sook
MS
Seo
Department of Chemistry and Nano Science, Center for Biomimetic Systems, Ewha Womans University, Seoul 03760, Korea.
Kyung-Bin
KB
Cho
Department of Chemistry, Faculty of Science, Gazi University, Ankara 06500, Turkey.
Yavuz
Y
Dede
Department of Chemistry, University of Nevada, Reno, Nevada 89557, USA.
Brenna C
BC
Keegan
Picobiology Institute, Graduate School of Life Science, University of Hyogo, RSC-UH LP Center, Hyogo 679-5148, Japan.
Takashi
T
Ogura
Western Seoul Center, Korea Basic Science Institute, Seoul 03759, Korea.
Sun Hee
SH
Kim
Picobiology Institute, Graduate School of Life Science, University of Hyogo, RSC-UH LP Center, Hyogo 679-5148, Japan.
Takehiro
T
Ohta
Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea.|Department of Chemistry, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea.
Mu-Hyun
0000-0002-8832-8187
MH
Baik
Department of Chemistry, Humboldt-Universität zu Berlin, Brook Taylor Strasse 2, Berlin 12489, Germany.
Kallol
K
Ray
Department of Chemistry, University of Nevada, Reno, Nevada 89557, USA.
Jason
J
Shearer
Department of Chemistry and Nano Science, Center for Biomimetic Systems, Ewha Womans University, Seoul 03760, Korea.|State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
Wonwoo
W
Nam