title: Synthesis and decarbonylation reactions of the triiron phosphinidene complex [Fe3Cp3(μ-H)(μ3-PPh)(CO)4]: easy cleavage and formation of P-H and Fe-Fe bonds.
abstract: The binuclear phosphine complex [Fe(2)Cp(2)(μ-CO)(2)(CO)(PH(2)Ph)] (Cp = η(5)-C(5)H(5)) reacted with the acetonitrile adduct [Fe(2)Cp(2)(μ-CO)(2)(CO)(NCMe)] in dichloromethane at 293 K to give the trinuclear hydride-phosphinidene derivative [Fe(3)Cp(3)(μ-H)(μ(3)-PPh)(CO)(4)] as a mixture of cis,anti and trans isomers (Fe-Fe = 2.7217(6) Å for the cis,anti isomer). In contrast, photochemical treatment of the phosphine complex with [Fe(2)Cp(2)(CO)(4)] gave the phosphide-bridged complex trans-[Fe(3)Cp(3)(μ-PHPh)(μ-CO)(2)(CO)(3)] as the major product, along with small amounts of the binuclear hydride-phosphide complexes [Fe(2)Cp(2)(μ-H)(μ-PHPh)(CO)(2)] (cis and trans isomers), which are more selectively prepared from [Fe(2)Cp(2)(CO)(4)] and PH(2)Ph at 388 K. The photochemical decarbonylation of either of the mentioned triiron compounds led reversibly to three different products depending on the reaction conditions: (a) the 48-electron phosphinidene cluster [Fe(3)Cp(3)(μ-H)(μ(3)-PPh)(μ-CO)(2)] (Fe-Fe = 2.592(2)-2.718(2) Å); (b) the 50-electron complex [Fe(3)Cp(3)(μ-H)(μ(3)-PPh)(μ-CO)(CO)(2)], also having carbonyl- and hydride-bridged metal-metal bonds (Fe-Fe = 2.6177(3) and 2.7611(4) Å, respectively); and (c) the 48-electron phosphide cluster [Fe(3)Cp(3)(μ-PHPh)(μ(3)-CO)(μ-CO)(2)], an isomer of the latter phosphinidene complex now having three intermetallic bonds (Fe-Fe = 2.5332(8)-2.6158(8) Å).
authors: Departamento de Química Orgánica e Inorgánica/IUQOEM, Universidad de Oviedo, E-33071 Oviedo, Spain.
authors: Celedonio M
authors: CM
authors: Alvarez
authors: M Angeles
authors: MA
authors: Alvarez
authors: M Esther
authors: ME
authors: García
authors: Rocío
authors: R
authors: González
authors: Alberto
authors: A
authors: Ramos
authors: Miguel A
authors: MA
authors: Ruiz