28630-04-8

Upstream product

• 26061-40-5 trans-{FeH(N₂)(depe)2}B(C₆H₅)4 
• 100-47-0 benzonitrile 
• 22763-25-3 trans-chlorobis(ethane-1,2-bis(diethylphosphine-P))hydridoiron(II) 
• 108150-67-0 trans-{Fe(H)(η2-H2)(depe)2}BPh4 
• 26061-40-5 FeH(N₂)((C₂H₅)2PCH₂CH₂P(C₂H₅)2)2⁽¹⁺⁾*B(C₆H₅)4^(1-) = [FeH(N₂)((C₂H₅)2PCH₂CH₂P(C₂H₅)2)2]B(C₆H₅)4 

Relevant academic research and scientific papers

The mechanism of displacement of dihydrogen and dinitrogen from iron, ruthenium and osmium hydrides and implications for models of nitrogenase action

The substitution of dihydrogen in complexes [FeH(H2)(phosphine)x]+ [phosphine = R2PCH2CH2PR2 (R = Et or Me) or P(CH2CH2PR′2)3 (R′ = Me or Ph)] by ligands L (MeCN, PhCN, or Cl-) has been shown to be first order in the concentration of complex and zero order in the concentration of L, in both acetone and thf. Activation parameters have been determined, and the mechanism of substitution is proposed to involve rate-determining loss of H2 from the parent complexes and subsequent rapid co-ordination of L. This mechanism differs from that recently proposed for an analogous complex of Ph2PCH2CH2PPh2, and the reasons for this are discussed. Less thorough studies of some related dinitrogen complexes, and of some homologous complexes of Ru and Os, are consistent with a similar loss of dinitrogen or dihydrogen being rate determining.

Mechanistic Studies on Iron Phosphine Complexes. Part 1. Protonation and Substitution of trans- (X=Cl or Br, diphosphine=Et2PCH2CH2PEt2 or Ph2PCH2CH2PPh2)

The mechanisms of protonation and substitution of trans- have been investigated in tetrahydrofuran at I=0.1 mol dm-3(n4>) and 25 deg C.In the presence of acid, HX, loss of phosphine and formation of occurs by a variety of pathways dependent upon the nature of the phosphine.When diphosphine=dppe rapid ring opening of the chelate from trans- allows protonation of the pendant phosphorus atom.Subsequent dissociation of the phosphine ligand, and protonation of the metal, with release of dihydrogen, results in the formation of .When diphosphine=depe a further pathway involving initial protonation of the metal is identifiable.In contrast, substitution of trans- by L=CO, MeCN, or PhCN to yield trans-+ has to await the slow dissociation of halide.

Mechanistic Studies on Iron Phosphine Complexes. Part 2. Protonation and Substitution Reactions of Dinitrogen Complexes

The mechanisms of the reactions of acid (HCl or HBr) or the nucleophiles CO, MeCN, or PhCN with trans-+ and trans-2(μ-N2)>2+ (depe=Et2PCH2CH2PEt2) have been investigated in tetrahydrofuran (I=0.1 mol dm-3, n4>; 25.0 deg C).In the reactions with acid, rapid phosphine chelate ring opening, from each iron complex, permits protonation of the pendant phosphorus atom, and ultimate loss of the phosphine ligand.In contrast, the mechanisms of the reactions of the nucleophiles L=CO, MeCN, or PhCN depend on the iron complex.Substitution of the bridged-dinitrogen ligand in trans-2(μ-N2)>2+ occurs, in general, by two parallel pathways.After initial phosphine chelate ring opening the vacant site thus generated can be attacked either by a molecule of solvent or the nucleophile.Subsequent loss of dinitrogen and phosphine chelate ring closure (and for the solvent route, displacement of the co-ordinated solvent by a molecule of the nucleophile) yields the product trans-+.Despite the rapid phosphine chelate ring-opening reaction associated with trans-+, substitution of the dinitrogen ligand by nucleophiles proceeds by a much slower pathway involving initial rate-limiting dissociation of dinitrogen.The reasons for the change in substitution mechanism between the mononuclear and binuclear complexes are discussed.