40697-11-8Relevant academic research and scientific papers
Synthesis and reactivity of acylphosphine tetracarbonyl-iron complexes
Brunet, Jean-Jacques,Chauvin, Remi,Donnadieu, Bruno,Thepaut, Erwan
, p. 198 - 205 (2007/10/03)
A general method for the synthesis of (CO)4Fe[PPhX(C(O)R)] complexes from lithium acylferrates and PhXPCl is described (R = alkyl, phenyl, X = Ph, Cl). The X-ray crystal structure of (CO)4Fe[PPh2(C(O)Me)] has been determined and compared with that of other mononuclear acylphosphine complexes, which all possess a long P-C(O) bond. The weakness of this bond is revealed in nucleophilic and basic media, where (CO)4Fe[PPh2(C(O)R)] mostly leads to the [(CO)4FePPh2]- anion. In the presence of LDA, however, some deprotonation occurs for R = Me, n-Bu, and subsequent addition of Ph2PCl leads to monodentate α-phosphinoxyvinyl phosphine carbonyliron complexes in moderate yield.
A Facile, high-yield synthesis of trans-Fe(CO)3(PR3)2 from Fe(CO)5, Fe(CO)4CHO-, HFe(CO)4-, or HFe(CO)3PR3-
Keiter, Richard L.,Keiter, Ellen A.,Hecker, Karl H.,Boecker, Carol A.
, p. 2466 - 2469 (2008/10/08)
The reaction of Fe(CO)5 with PR3 and NaBH4 in refluxing n-butyl alcohol affords high yields of trans-Fe(CO)3(PR3)2. It has been shown that Fe(CO)4PR3, which does not appear in the collected product, is also not a significant intermediate in the reaction. The reaction proceeds by initial formation of H2 gas and Fe(CO)4CHO-. The formyl complex decomposes to HFe(CO)4- which reacts with PR3 to give the disubstituted product. The principal intermediate for this substitution is believed to be HFe(CO)3PR3-, although polynuclear species may also be important. The substitution of HFe(CO)4- by PR3 is favorable when the counterion is Na+ but not when it is PPN+. The overall reaction is very sensitive to choice of solvent; substitution of ethanol for n-butyl alcohol leads to greatly reduced yields.
Binuclear phosphido-bridged complexes that link titanium and zirconium to tungsten and iron. Crystal and molecular structure of ZrW(μ-PPh2)2Cp2(CO)4
Targos, Tom S.,Rosen, Richard P.,Whittle, Robert R.,Geoffroy, Gregory L.
, p. 1375 - 1379 (2008/10/08)
The new complexes ZrW(μ-PPh2)2Cp2(CO)4, ZrFe(μ-PR2)2Cp2(CO)3 (R = Ph, cyclohexyl), TiW(μ-PPh2)2Cp′2(CO)4 (Cp′ = C5H4CH3), and TiFe(μ-PPh2)2Cp′2(CO)3 have been prepared by the reaction of Li2[W(CO)4(PPh2)2] and Li2[Fe(CO)3(PR2)2] with Cp2ZrCl2 and Cp′2TiCl2. They have been spectroscopically characterized, and ZrW(μ-PPh2)2Cp2(CO)4 has been further defined by an X-ray diffraction study. It crystallizes in the space group P21/c with a = 14.644 (4) A?, b = 16.932 (4) A?, c = 17.003 (3) A?, β = 100.13 (2)°, V = 4150 (3) A?3, and Z = 4. The structure refined to R = 0.047 and Rw = 0.067 for the 3340 reflections with I > 2σ(I). The W and Zr atoms are bridged by two μ-PPh2 ligands with the Zr further coordinated by two η5-C5H5 ligands and the W by four CO's. The Zr center has a pseudotetrahedral coordination geometry, and W has a nearly perfect octahedral ligand arrangement. The W-Zr distance is 3.289 (1) A?, implying a weak metal-metal interaction at best.
