88211-53-4

Upstream product

• 73690-56-9 W(CO)3(PCy₃)2 
• 1333-74-0 hydrogen 
• 104198-75-6 (η2-dihydrogen)W(CO)3(tricyclohexylphosphine)2 

Downstream Products

• 131617-33-9 HW(BF₄)(CO)3(P(C₆H₁₁)3)2 

Relevant academic research and scientific papers

Direct measurements of rate constants and activation volumes for the binding of H2, D2, N2, C2H 4, and CH3CN to W(CO)3(PCy3) 2: Theoretical and experimental studies with time-resolved step-scan FTIR and UV-Vis spectroscopy

Pulsed 355 nm laser excitation of toluene or hexane solutions containing W-L (W = mer,trans-W(CO)3(PCy3)2; PCy 3 = tricyclohexylphosphine; L = H2, D2, N 2, C2H4, or CH3CN) resulted in the photoejection of ligand L and the formation of W. A combination of nanosecond UV-vis flash photolysis and time-resolved step-scan FTIR (s2-FTIR) spectroscopy was used to spectroscopically characterize the photoproduct, W, and directly measure the rate constants for binding of the ligands L to W to reform W-L under pseudo-first-order conditions. From these data, equilibrium constants for the binding of L to W were estimated. The UV-vis flash photolysis experiments were also performed as a function of pressure in order to determine the activation volumes, ΔV?, for the reaction of W with L. Small activation volumes ranging from -7 to -3 cm3 mol-1 were obtained, suggesting that despite the crowded W center an interchange mechanism between L and the agostic W...H-C interaction of one of the PCy3 ligands (or a weak interaction with a solvent molecule) at the W center takes place in the transition state. Density functional theory (DFT) calculations were performed at the B3LYP level of theory on W with/without the agostic C-H interaction of the PCy3 ligand and also on the series of model complexes, mer,trans-W(CO)3(PH3)2L (W′-L, where L = H2, N2, C2H4, CO, or n-hexane) in an effort to confirm the infrared spectroscopic assignment of the W-L complexes, to simulate and assign the electronic transitions in the UV-vis spectra, to determine the nature of the HOMO and LUMO of W-L, and to understand the agostic C-H interaction of the ligand vs solvent interaction. Our DFT calculations indicate an entropy effect that favors agostic W...H-C interaction over a solvent σ C-H interaction by 8-10 kcal mol -1.

Molecular hydrogen complexes of the transition metals. 7. Kinetics and thermodynamics of the interconversion between dihydride and dihydrogen forms of W(CO)3(PR3)2H2 where R = isopropyl and cyclopentyl

Kinetic and thermodynamic parameters have been obtained for the equilibrium system H2W(CO)3(PR3)2 ? W(CO)3(PR3)2(η2-H2). The systems studied include a newly