16632-93-2

Upstream product

• 176260-44-9 [Mo(CO)5(C₂₄H₁₆N₂)] 
• 1662-01-7 bathophenanthroline 
• 13939-06-5 molybdenum hexacarbonyl 

Downstream Products

• 390387-45-8 [molybdenum(CO)2(4,7-diphenyl-1,10-phenanthroline)(dibutylfumarate)2] 

Relevant academic research and scientific papers

A molybdenum complex with 4,7-diphenyl-1,10-phenanthroline

In the title compound, tetracarbonyl(4,7-diphenyl-1,10-phenanthroline-N,N′)molybdenum(0), [Mo(C24H16N2)(CO)4], the Mo-atom coordination is distorted octahedral, with two CO groups cis to each other, but each trans to an N atom of the 4,7-diphenyl-1,10-phenanthroline (dpphen) ligand, and with the other two CO groups trans to each other and on the axis position. The complex has better solubility than [Mo(phen)(CO)4], where phen is 1,10-phenanthroline.

A Quantitative Description of the σ-Donor and π-Acceptor Properties of Substituted Phenanthrolines

The bond between molybdenum and substituted 1,10-phenanthroline ligands in a series of [Mo(CO)4(phen*)] complexes has been studied by combining experimental data (νCO) with DFT calculations. First, natural orbitals for chemical valence (NOCV) were calculated: The resulting charge-transfer magnitudes (Δqi) associated with the deformation density channels (Δ?i) were related to σ-donation and π-back-donation. Then, energy decomposition analysis was performed by applying the extended transition state (ETS) scheme. The outcomes of the ETS-NOCV approach has allowed us to quantify the energetic contribution of both ligand-to-metal (Eσ) and metal-to-ligand (Eπ) interactions. A new parameter (Tphen) has been introduced comprising both Eσand Eπand thus providing a descriptor for the overall electronic contribution given by phenanthrolines to the metal–ligand bond. This was corroborated by the linear correlation found between Tphenand the νCOvibration modes of [Mo(CO)4(phen*)] complexes, at least for those containing a 2,9-unsubstituted phenanthroline. The case of [Mo(CO)4(phen*)] derivatives with a 2,9-substituted phen* is also discussed.

Mechanism of chelation of phenanthroline derivatives to Mo(CO)5 deduced from pulsed photolysis studies in several solvents at high pressure

A laser flash-photolysis kinetic study has been carried out on the concentration, temperature and pressure dependence of chelation reactions of the type +CO, where L-L represents 1,10-phenanthroline (phen) and a series of substituted phen ligands in several solvents.The activation parameters for these thermal ring-closure reactions are sensitive to the nature of the solvent, as well as to electronic and steric effects arising from the phen ligand.All the observed kinetic effects can be accounted for by an interchange ligand-substitution mechanism during which CO is displaced by the chelate.

Photolysis of group 6 metal hexacarbonyl solutions containing diimine ligands. Spectral characterization and reaction kinetics of a photoproduced intermediate, monodentate M(CO)5(diimine)

Electronic absorption spectra have been obtained immediately following the photolysis of M(CO)6 solutions containing diimine ligands (1,10-phenanthroline, 2,2′-bipyridine, 1,4-diazabutadiene, or their derivatives) with the use of a microprocessor-controlled diode-array UV-visible spectrophotometer. The time-dependent spectra illustrate rapid formation of a reaction intermediate that is assigned to be M(CO)5L, where L is a diimine ligand coordinated in a monodentate fashion. Monodentate M(CO)5L subsequently extrudes CO thermally via a first-order kinetic process to form stable M(CO)4L. No discernable M(CO)5L intermediates were observed when L = 1,10-phenanthroline (phen) or a phen derivative consistent with the rigid coplanar nature of these ligands. In contrast, the chelation of M(CO)5L complexes, where L = 2,2′-bipyridine, 1,4-diazabutadiene, or derivatives, proceeds with considerably slower reaction rates. The rate data are interpreted in terms of the stereochemistry of the monodentate intermediate. For a given ligand, the reaction rate decreases in the sequence Mo > Cr > W, analogous to the order of CO release in M(CO)6; this ordering suggests that the predominant barrier to chelation involves breaking of the M-C bond. Derived activation energy parameters indicate that the chelation reaction is enthalpy-controlled. The marked dependence of reaction rate on diimine and resulting negative activation entropy values imply that the chelation mechanism proceeds with a substantial associative component.