Premium
Stabilization of a Two‐Coordinate Mononuclear Cobalt(0) Compound
Author(s) -
Mondal Kartik Chandra,
Roy Sudipta,
De Susmita,
Parameswaran Pattiyil,
Dittrich Birger,
Ehret Fabian,
Kaim Wolfgang,
Roesky Herbert W.
Publication year - 2014
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201403525
Subject(s) - cobalt , electron paramagnetic resonance , chemistry , crystallography , carbene , atom (system on chip) , bond length , resonance (particle physics) , stereochemistry , crystal structure , nuclear magnetic resonance , catalysis , physics , inorganic chemistry , atomic physics , organic chemistry , computer science , embedded system
Compound (Me 2 ‐cAAC:) 2 Co 0 ( 2 ; Me 2 ‐cAAC:=cyclic (alkyl) amino carbene; :C(CH 2 )(CMe 2 ) 2 N‐2,6‐ i Pr 2 C 6 H 3 ) was synthesized by the reduction of the precursor (Me 2 ‐cAAC:) 2 Co I Cl ( 1 ) with KC 8 in THF. The cyclic voltammogram of 1 exhibited one‐electron reduction, which suggests that synthesis of a bent 2‐metallaallene ( 2 ) from 1 should be possible. Compound 2 contains one cobalt atom in the formal oxidation state zero, which is stabilized by two Me 2 ‐cAAC: ligands. Bond lengths from X‐ray diffraction are 1.871(2) and 1.877(2) Å with a C‐Co‐C bond angle of 170.12(8)°. The EPR spectrum of 2 exhibited a broad resonance attributed to the unique quasi‐linear structure, which favors near degeneracy and gives rise to very rapid relaxation conditions. The cAACCo bond in 2 can be considered as a typical Dewar–Chatt–Duncanson type of bonding, which in turn retains 2.5 electron pairs on the Co atom as nonbonding electrons.