Thermal ring closure in Mo(CO){sub 5}L (L = bpy, dmbpy, dpbpy) transients generated by pulsed laser flash photolysis. Mechanistic information from high-pressure effects
- Univ. of Utah, Salt Lake City, UT (United States)
The kinetics of the ring-closure reactions of Mo(CO){sub 5}L, produced during the laser flash photolysis of Mo(CO){sub 6} and L where L = 2,2{prime}-bipyridine (bpy), 4,4{prime}-dimethyl-2,2{prime}-bipyridine (dpbpy) and 4,4{prime}-dephenyl-2,2{prime}-bipyridine (dpbpy) were studied as a function of temperature and pressure. The values of the activation parameters and pressure. The values of the activation parameters {Delta}S and {Delta}V are small and negative for L = bpy and dmbpy supporting an associative interchange mechanism (I{sub a}) for CO extrusion. For L = dpbpy, {Delta}V is small and positive in line with a dissociative interchange mechanism (I{sub d}). The results demonstrate a changeover in mechanism from I{sub a} to I{sub d} with increasing steric hindrance on the bidentate ligand L. 36 refs., 1 fig., 2 tabs.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 458738
- Journal Information:
- Organometallics, Vol. 11, Issue 6; Other Information: PBD: Jun 1992
- Country of Publication:
- United States
- Language:
- English
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