Solution Thermochemical Studies Of Organomolybdenum Complexes

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Degree Name

Doctor of Philosophy (Ph.D.)




The results of solution calorimetric studies are used to measure the relative stabilities in solution of five related systems. Enthalpies of substitution for the fac -LnMo(CO)$\sb3$ and cis -LnMo(CO)$\sb4$ systems have been investigated for a wide range of ligands, L: olefins, arenes, acetone, diglyme, nitriles, isonitriles, phosphines and carbon monoxide. Bond strength estimates for all these complexes are reported and span a range of 50 and 33 kcal/mole for fac -LnMo(CO)$\sb3$ and cis -LnMo(CO)$\sb4$, respectively. The heats of reaction of H-Mo(CO)$\sb3$C$\sb5$H$\sb5$ with CX$\sb4$ (X = Cl,Br) producing XMo(CO)$\sb3$C$\sb5$H$\sb5$ and of NaMo(CO)$\sb3$C$\sb5$H$\sb5$ with CH$\sb3$ I and I$\sb2$ are reported and bond dissociation energies are estimated for these species. The enthalpy of cabonyl insertion is calculated from solution calorimetric work on the phosphine substitution of H-Mo(CO)$\sb3$C$\sb5$H$\sb5$ and the phosphine promoted CO insertion reaction in the system R-Mo(CO)$\sb3$C$\sb5$H$\sb5$ (R = Me,Et). Based on the reaction of the triple bonded dimer (Mo(CO)$\sb2$C$\sb5$H$\sb5$) $\sb2$ with carbon monoxide, an estimate of the strength of this triple bond is reported. Using the bond dissociation energies obtained in these studies, enthalpies of reaction and equilibrium constants of important organometallic reactions are estimated.


Chemistry, Inorganic

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