97390-96-0Relevant academic research and scientific papers
Electron transfer from borohydride and selective reductions of iron cations. Synthesis of tetrathiooxalate iron derivatives
Touchard, Daniel,Fillaut, Jean-Luc,Khasnis, Dilip V.,Dixneuf, Pierre H.,Mealli, Carlo,Masi, Dante,Toupet, Lo?c
, p. 67 - 75 (2008/10/08)
Cations of the type Fe(η2-CS2R)(CO)2(L)2+ (L = PPh3; R = Me (2a), Et (2b), CH2C(Me)=CH2 (2c)) react with NaBH4 to afford, via electron transfer, C-C coupling products (RS)2C2S2Fe2(CO)4(L) 2 (3a-c). Complexes 2 containing an acylalkyl group, R, also give complexes 3d,e, but only on reduction with activated magnesium. Reduction of cations 2a-c with sodium amalgam leads first to 3a-c and then to the (RS)2C2S2Fe(CO)2(L) complexes (4). Complexes 4a-c are also obtained on treatment of 3a-c with Lewis acids in the presence of air. Cation 2h (L = P(OMe)3, R = Me) is less easily reduced (Ec = -0.81 V vs SCE) than 2a (L = PPh3; Ec = -0.74 V vs SCE) and, when treated with NaBH4, undergoes electron transfer and hydride addition: complex 6, analogous to 3, and Fe(η2-HCS2Me)(CO)2L2 (5) are thus formed. Reaction of 2h with Na/Hg affords by contrast small amounts of FeCS(CO)2L2 (8) and (R2S)2C2S2Fe(CO)L2 (9). The X-ray diffraction structures of 3a and 4a have been determined. 3a: space group P1, Z = 2, a = 9.669 (2) A?, b = 13.477 (3) A?, c = 17.323 (3) A?, α = 101.1 (2)°, β = 91.5 (2)°, γ = 110.3 (2)°, V = 2048 A?3, R = 0.058 for 3802 reflections having I > σ(I). 4a: space group P21/a, Z = 4, a = 24.144 (6) A?, b = 10.017 (2) A?, c = 10.745 (2) A?, α = 97.38 (2)°, V = 2577 A?3, R = 0.084 for 2440 reflections having I > 3σ(I).
Electron-promoted C-C bond formation. Novel route to tetrathlooxalate derivatives
Touchard, Daniel,Fillaut, Jean-Luc,Dixneuf, Pierre,Mealli, Carlo,Sabat, Michal,Toupet, Lolc
, p. 1684 - 1686 (2008/10/08)
The addition of NaBH4 in THF to [Fe(η2-CS2Me)(CO)2L2] +PF6- (1b, L = PPh3) gave the purple complex Fe2(μ-η2-S2C2(SMe) 2)(CO)4(PPh3)2 (3, 68%), whereas 1a (L = PMe3) under the same conditions afforded Fe(η2-HCS2Me)(CO)2(PMe3) 2 (2a). Complex 3 was transformed by exposure to air into a blue derivative, Fe(η2-S2C2(SMe)2)(CO) 2PPh3 (4, 30-48%), the latter reaction being accelerated by the presence of acids, Na+-PF6-, or H2O2. By treatment with sodium amalgam complex 1b also gave 3 which was transformed in situ into 4. These reactions are consistent with electron transfer from hydride (or Na/Hg) to 1b, C-C bond formation of the resulting radical giving 3 and oxidative cleavage of the Fe-Fe bond of 3 to produce 4. X-ray structure characterizations of 3 and 4 are reported.
