96041-51-9Relevant academic research and scientific papers
Photochemical reactions of Re2(CO)9L, 1,2-Re2(CO)8L2, and Re2(CO)8(μ-L L) with Alkenes
Lee, Kang-Wook,Brown, Theodore L.
, p. 1030 - 1036 (2008/10/08)
The photochemical reactions of Re2(CO)9L (L = PMe3, PPh3) with ethylene give (μ-H)Re2(CO)8(μ-CH=CH2), (μ-H)Re2(CO)7(μ-CH=CH2)L (1, L = PMe3; 2, L = PPh3) and (μ-H)Re2(CO)6(M-CH=CH2)L2 (3a, L - PMe3; 3b, L = PPh3). There are four isomers each of 1 and 2 relating to the locations of the phosphine ligand. Photolysis of 1,2-Re2(CO)8L2 (L = PMe3, PPh3) in the presence of ethylene yields mainly 3a or 3b. The equivalent reaction of a 3:2 mixture of Re2(CO)10 and 1,2-Re2(CO)8(PMe3)2 yields (μ-H)-Re2(CO)8(μ-CH=CH2) and 1; that of the 1:1 mixture of 1,2-Re2(CO)8(PMe3)2 and 1,2-Re2(CO)8(PPh3)2 gives (μ-H)Re2(CO)6(μ-CH=CH2)(PMe 3)(PPh3) as one of several products. The results are consistent with metal-metal bond cleavage as the important primary photoprocess. The photochemical reactions of Re2(CO)8(μ-dmpm), -(μ-dppe), and -(μ-dmpe) with H2C=CHR (R = H, Me) proceed very slowly to give (μ-H)Re2(CO)6(μ-dmpm)(μ-CH=CHR), 4, (μ-H)Re2(CO)6(μ-CH=CHR)(dppe), 5, and (μ-H)Re2(CO)6(μ-LH=CHR)(dmpe), 6. These reactions appear to proceed mainly by photodissociation of CO. Coordination of dmpe and dppe has undergone rearrangement to a chelate configuration. The μ-alkenyl ligand of 4 undergoes a rapid fluxional process at ambient temperature in which the σ- and π-bonds of the alkenyl group are interchanged between the bridged rhenium atoms.
