367493-49-0Relevant academic research and scientific papers
Preparation, spectroscopic properties, and crystal structures of Fe2(CO)6(μ-CO)(μ-CF2)2, Fe2(CO)6(μ-CO)2(μ-CF2), and Fe2(CO)6(μ-CF2)(PPh3)2 - Theoretical studies of methylenic vs. carbonyl bridges in diiron complexes
Petz
, p. 1859 - 1869 (2001)
The reaction of Na2[Fe(CO)4] with Br2CF2 in n-pentane generates a mixture of the compounds (CO)3Fe(μ-CO)3-n(μ-CF2) nFe(CO)3 (2, n = 2; 3, n = 1) in low yields with 3 as the main product. 3 is obtained free from 2 by reacting Br2CF2 with Na2[Fe2(CO)8]. The non-isolable monomeric complex (CO)4Fe=CF2 (1) can probably considered as the precursor for 2. 3 reacts with PPh3 with replacement of two CO ligands to form Fe2(CO)6(μ-CF2)(PPh3)2 (4). The complexes 2-4 were characterized by single crystal X-ray diffraction. While the structure of 2 is strictly similar to that of Fe2(CO)9, the structure of 3 can better be described as a re suiting from superposition of the two enantiomers 3a and 3b with two semibridging CO groups. Quantum chemical DFT calculations for the series (CO)3Fe(μCO)3-n(μ-CF2) nFe(CO)3 (n = 0, 1, 2, 3) as well as for the corresponding (μ-CH2) derivatives indicate that the progressively larger σ donor and π acceptor properties for the bridging ligands, in the order CO 2 2, favor a stronger Fe-Fe bond. WILEY-VCH Verlag GmbH, D-69451 Weinheim, 2001.
