24554-78-7

Upstream product

• 24554-47-0 bis(phenyldimethylphosphine)molybdenum tetracarbonyl 
• 80410-03-3 cis-(triphenylphosphine)(dimethylphenylphosphine) tetracarbonyl molybdenum 
• 80410-02-2 Mo(CO)4(NHC₅H₁₀)P(C₆H₅)(CH₃)2 

Relevant academic research and scientific papers

Structural characterizations of cis-Mo(CO)4(PPhMe2)(NHC5H10) and cis-Mo(CO)4(PPhMe2)(PPh3) and their solution reactivities toward carbon monoxide

The crystal and molecular structures of cis-Mo(CO)4(PPhMe2)(HNC5H10) (1) and cis-Mo(CO)4(PPhMe2)(PPh3) (2) have been determined and are discussed in terms of the influence of structural and steric factors on the reactivities of cis-Mo(CO)4L2 molecules. Compound 1 forms monoclinic crystals in space group P21/c with a = 13.764 (3) ?, b = 10.693 (2) ?, c = 13.585 (2) ?, β = 98.99 (2)°, V = 1974 (1) ?3, and Z = 4. The structure was refined to R1 = 0.038. Compound 2 forms monoclinic crystals in space group P21/n with a = 9.487 (1) ?, b = 17.757 (2) ?, c = 16.920 (1) ?, β = 98.72 (1)°, V = 2817.5 (5) ?3, and Z = 4. The structure was refined to R1 = 0.030. The 13C NMR spectra have also been recorded, and they show that 31P-13C couplings are in the ranges 7.8-9.8 Hz for the cis arrangement and 24.2-31.3 Hz for the trans arrangement and that chemical shifts are increasingly downfield as the Mo-C bond lengths become shorter. Relative rates of reaction of the cis-Mo(CO)4LL′ compounds with CO to give Mo(CO)5PMe2Ph are found to correlate well with steric factors.

Steric contributions to the solid-state structures of bis(phosphine) derivatives of molybdenum carbonyl. X-ray structural studies of cis-Mo(CO)4[PPh3-nMen]2 (n = 0, 1, 2)

The crystal and molecular structures of three cis-Mo(CO)4(PR3)2 compounds - PR3 = PMe2Ph (1), PR3 = MePh2 (2), and PPh3 = PR3 (3) - have been determined to provide data for assessing the influence of steric effects on the stability and reactivity of such molecules. In the order 1, 2, 3, the following changes occur: 〈P-Mo-P = 94.78 (5), 92.52 (5), 104.62 (7)°; r(Mo-P) = 2.529 (3), 2.555 (5), 2.577 (2) A?. The irregularity in the angle changes is probably due to the rotational orientations of the ligands in 1 and 2 and may be characteristic of the solid state only. Crystallographic data are as follows. 1: P212121 with a = 8.203 (1) A?, b = 9.795 (1) A?, c = 27.604 (4) A?, V = 2217 (1) A?3, Z = 4. 2: Pc with a = 9.648 (2) A?, b = 10.670 (3) A?, c = 14.065 (1) A?, β = 98.22 (1)° V = 1433 (1) A?3, Z = 2. 3: P1 with a = 11.522 (1) A?, b = 16.909 (3) A?, c = 9.633 (2) A?, α = 98.05 (2)°, β = 110.29 (1)°, γ = 99.95 (1)°, V = 1693 (1) A?3, Z = 2. The steric and electronic factors that may affect the molecular structures are discussed, and it is shown that steric factors play a key role (affecting also the chemical reactivity) but not in a quantitatively predictable way.