96191-64-9Relevant academic research and scientific papers
Absolute rate expressions for hydrogen atom abstraction from molybdenum hydrides by carbon-centered radicals
Franz, James A.,Linehan, John C.,Birnbaum, Jerome C.,Hicks, Kenneth W.,Alnajjar
, p. 9824 - 9830 (1999)
A new family of basis rate expressions for hydrogen atom abstraction by primary, secondary, and tertiary alkyl radicals in dodecane and benzyl radical in benzene from the molybdenum hydride Cp*Mo(CO)3H and for reactions of a primary alkyl radical with CpMo(CO)3H in dodecane are reported (Cp* = η5-pentamethylcyclopentadienyl, Cp = η5-cyclopentadienyl). Rate expressions for reaction of primary, secondary, and tertiary radical clocks with Cp*Mo(CO)3H were as follow: for hex-5-enyl, log(kl/M-1 s-1) = (9.27 ± 0.13) - (1.36 ± 0.22)/θ, θ = 2.303RT kcal/mol; for hept-6-en-2-yl, log(k/M-1 s-1) = (9.12 ± 0.42) - (1.91 ± 0.74)/θ; and for 2-methylhept-6-en-2-yl, log(k/M-1 s-1) = (9.36 ± 0.18) - (3.19 ± 0.30)/θ (errors are 2σ). Hydrogen atom abstraction from CpMo(CO)3H by hex-5-enyl is described by log(k/M-1 s-1) = (9.53 ± 0.34) - (1.24 ± 0.62)/θ. Relative rate constants for 1°:2°:3° alkyl radicals were found to be 26:7:1 at 298 K. Benzyl radical was found to react 1.4 times faster than tertiary alkyl radical. The much higher selectivities for Cp*Mo(CO)3H than those observed for main group hydrides (Bu3SnH, PhSeH, PhSH) with alkyl radicals, together with the very fast benzyl hydrogen-transfer rate, suggest the relative unimportance of simple enthalpic effects and the dominance of steric effects for the early transition-state hydrogen transfers. Hydrogen abstraction from Cp*Mo(CO)3H by benzyl radicals is described by log(k/M-1 s-1) = (8.89 ± 0.22) - (2.31 ± 0.33)/θ.
CARBON MONOXIDE INSERTION REACTIONS IN SUBSTITUTED CYCLOPENTADIENYLMOLYBDENUM COMPLEXES
Cotton, J. D.,Kimlin, H. A.
, p. 213 - 218 (2007/10/02)
The reactions of 5-C5Me5)(CO)3MoCH2Ph> and 5-C5H4Me)(CO)3MoCH2Ph> with tertiary phosphines and alkyl isocyanides in polar solvents to yield phosphine-substituted molybdenum acyl complexes have been explored and compared with the behaviour of the unsubstituted cyclopentadienyl compound.For the pentamethylcyclopentadienyl complex, reaction is restricted to tertiary phosphines with small cone angles.Unlike the cyclopentadienyl system, a mixture of cis- and trans-acyl products is formed.
