138124-34-2Relevant academic research and scientific papers
Paramagnetic organometallic molecules. 16. ESR studies of cobalt acetylene π complexes: A new class of fluxional organocobalt radicals
Casagrande, Louis V.,Chen, Taicheng,Rieger, Philip H.,Robinson, Brian H.,Simpson, Jim,Visco, Steven J.
, p. 2019 - 2025 (2008/10/08)
ESR studies are reported on 19 radicals of the general formula (R2C2)Co(CO)3-xLx where L is a phosphine, phosphite, or arsine and x = 0-3. The radicals are obtained by reduction of THF solutions of acetylene-bridged dicobalt clusters, R2C2Co2(CO)6-xLx, in the presence of excess ligand L and, for x = 2 or 3, are long-lived at room temperature. ESR line width studies show the radicals (Ph2C2)Co(CO)[P(OMe)3]2 to be very rapidly fluxional (τ = 2.2 × 10-11 s at 290 K) with instantaneously nonequivalent phosphite ligands. Analysis of the frozen-solution ESR spectrum of (t-Bu2C2)Co(CO)2P-n-Bu3 permits detailed characterization of the semioccupied molecular orbital. A pseudo-square-planar molecular structure can be inferred from the ESR results.
