A Two-Coordinate Cobalt(II) Imido Complex with NHC Ligation: Synthesis, Structure, and Reactivity.

Angew Chem Int Ed Engl

State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032 (P.R. China) http://dengliang.sioc.ac.cn/.

Published: October 2015

The synthesis, structural characterization, and reactivity of the first two-coordinate cobalt complex featuring a metal-element multiple bond [(IPr)Co(NDmp)] (4; IPr=1,3-bis(2',6'-diisopropylphenyl)imidazole-2-ylidene; Dmp=2,6-dimesitylphenyl) is reported. Complex 4 was prepared from the reaction of [(IPr)Co(η(2) -vtms)2 ] (vtms=vinyltrimethylsilane) with DmpN3 . An X-ray diffraction study revealed its linear C-Co-N core and a short Co-N distance (1.691(6) Å). Spectroscopic characterization and calculation studies indicated the high-spin nature of 4 and the multiple-bond character of the Co-N bond. Complex 4 effected group-transfer reactions to CO and ethylene to form isocyanide and imine, respectively. It also facilitated E-H (E=C, Si) σ-bond activation of terminal alkyne and hydrosilanes to produce the corresponding cobalt(II) alkynyl and cobalt(II) hydride complexes as 1,2-addition products.

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http://dx.doi.org/10.1002/anie.201505937DOI Listing

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A Two-Coordinate Cobalt(II) Imido Complex with NHC Ligation: Synthesis, Structure, and Reactivity.

Angew Chem Int Ed Engl

October 2015

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