131617-33-9Relevant academic research and scientific papers
Protonation of W(CO)3(PCy3)2
Van Der Sluys, Lori Stepan,Kubat-Martin, Kimberly A.,Kubas, Gregory J.,Caulton, Kenneth G.
, p. 306 - 310 (2008/10/08)
Protonation of W(CO)3(PCy3)2 with equimolar HBF4·OEt2 in toluene produces WH(BF4)(CO)3(PCy3)2. This was characterized by spectroscopic methods and single-crystal X-ray diffraction as a seven-coordinate molecule with η1-coordinated BF4-. The location of the hydride, in the WFP2CO plane and in the cis position relative to one P and CO, makes the phosphines inequivalent. This inequivalence is evident in both the 31P and 1H NMR spectra, but the onset of hydride fluxionality is detected already at 25°C. The low-temperature 19F NMR spectrum and also the comparison of the spectral data of this molecule to that of the analogous products from HO3SCF3, H2C(SO2CF3)2, and HCl·Et2O indicate that the conjugate base of the acid employed for protonation remains coordinated in aromatic solvents. Reactivity studies of W(CO)3P2 with BF4- are consistent with the idea that the overall protonation reaction of 16-electron W(CO)3(PCy3)2 is initiated by proton transfer, not by coordination of a lone pair of the conjugate base (e.g., BF4- or OEt2).
