356785-34-7Relevant academic research and scientific papers
Alcohol complexes of tungsten prepared by ionic hydrogenations of ketones
Song, Jeong-Sup,Szalda, David J.,Bullock, R. Morris
, p. 3337 - 3346 (2008/10/08)
Ionic hydrogenation of acetone by Cp(CO)3WH and HOTf (OTf = OSO2CF3) gives the 2-propanol complex [Cp(CO)3W(HOiPr)]+OTf-. 1H NMR data suggest O-H?O hydrogen bonding between the alcohol OH and an oxygen of the triflate anion in solution, and a crystal structure of this complex shows that hydrogen bonding also exists in the solid state. The short O?O distance of 2.63(1) ? indicates a strong hydrogen bond. Hydrogenation of other ketones and aldehydes gives related [Cp(CO)3W(alcohol)]+OTf complexes. Aldehydes are selectively hydrogenated over ketones, and alkyl ketones are selectively hydrogenated over aromatic ketones. Hydrogenation of acetophenone gives ethylbenzene, with no intermediate tungsten complexes being observed. Reaction of 1-phenyl-1,3-butanedione with Cp(CO)3WH and HOTf gave {Cp(CO)3W[CH3CH(OH)CH2C(=O)Ph]}+ OTf-, the structure of which was determined by X-ray diffraction. The alcohol complexes [Cp(CO)3W(alcohol)]+OTf- decompose in solution to give free alcohols and Cp(CO)3WOTf. The cationic dihydride [Cp(CO)2(PMe3-W(H)2]+OTf- hydrogenates aldehydes and ketones; in these reactions a metal hydride serves as both the proton and hydride donor.
