95648-64-9Relevant academic research and scientific papers
Binuclear rhenium complexes bridged by phosphine bidentate ligands, Re2(CO)6(μ-Ph2PCH2PPh 2)2, Re2(CO)6(μ-Ph2PCH2PPh 2)(μ-Me2PCH2PMe2), and Re2(CO)6(μ-Me2PCH ...
Lee, Kang-Wook,Brown, Theodore L.
, p. 1025 - 1030 (2008/10/08)
Full title: Binuclear rhenium complexes bridged by phosphine bidentate ligands, Re2(CO)6(μ-Ph2PCH2PPh 2)2, Re2(CO)6(μ-Ph2PCH2PPh 2)(μ-Me2PCH2PMe2), and Re2(CO)6(μ-Me2PCH2PMe 2)2. Preparation and reactions with alkynes, water, methanol, and a hydrogen donor. Re2(CO)6(μ-dppm)2, 1a, Re2(CO)6(μ-dppm)(μ-dmpm), 1b, and Re2(CO)6(μ-dmpm)2, 1c (dppm = Ph2PCH2PPh2; dmpm = Me2PCH2PMe2), were synthesized by thermal or photochemical reactions of Re2(CO)8(μ-L L) [L L = bis(diphenylphosphino)methane or bis(dimethylphosphino)methane] and L L. The carbonyl ligands in 1 do not undergo a scrambling process up to 100°C. The thermal reactions of 1a and 1b at high temperature (172°C) with phenylacetylene yield (μ-H)Re2(CO)4(μ-dppm)2(μ-C≡CPh), 2a, and (μ-H)Re2(CO)4(μ-dppm)(μ-dmpm) (μ-C≡CPh), 2b, respectively. Reflux of (μ-H)Re2(CO)6(μ-dppm)(μ-C≡CPh) and (μ-H)Re2(CO)6(M-dmpm)(μ-C≡CPh) in m-xylene with excess dppm quantitatively yields 2a and 2b, respectively. Reflux of 1a or 1b in m-dichlorobenzene in the presence of water or methanol yields (μ-H)Re2(CO)4(μ-dppm)2(μ-OR) (3a, R = H; 3b, R = Me) or (μ-H)Re2(CO)4(μ-dppm)(μ-dmpm)(μ-OR) (3c R = H; 3d, R = Me), respectively. Reflux of 1a or 1b in 1,2,4-trimethylbenzene results m the formation of (μ-H)2Re2(CO)4(μ-dppm)2,4a, or (μ-H)2Re2(CO)4(μ-dppm)(μ-dmpm), 4b, respectively. No evidence was found for a bridging carbonyl complex, Re2(CO)4(μ-CO)(μ-dppm)2. Reaction of 4a with CO or phenylacetylene at 138°C gives 1a or 2a, respectively. The alkynyl ligand in 2 undergoes a fluxional process. The 1H and 13C NMR spectral data of bridging dppm dirhenium carbonyl compounds are compared.
