Chemie polyfunktioneller moleküle CXXII. Das komplexchemische verhalten von bis(diphenylphosphino)amin gegenüber dieisennnonacarbonyl und reaktionen von [Fe 2(CO) 6(μ-CO)(μ-Ph 2P-NH-PPh 2)] · THF

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Treatment of [Fe 2(CO) 9] with bis(diphenylphosphino)amine, Ph 2PNHPPh 2, dppa ( 1) in THF yields [(OC) 4Fe(μ-dppa)Fe(CO) 4] ( 5) and [Fe 2(CO) 6(μ-CO)(μ-dppa)]·THF ( 6·THF). Further reaction of 6·THF with dppa gives [Fe 2(CO) 4(μ-CO)(μ-dppa) 2]·2 THF ( 9·2 THF) by CO-substitution, whereas P(n-Bu)Ph 2, PPh 3 and PMe 3 add themselves to 6 · THF by forming the linear complexes [(OC) 4Fe(μ-dppa)Fe(CO) 3P(n-Bu)Ph 2] (7a), [(OC) 4Fe(μ-dppa)Fe(CO) 3PPh 3] (7b) and [(OC) 4Fe(μ-dppa)Fe(CO) 3PMe 3] (7c). The reaction of 6 · THF with HPPh 2 or ClPPh 2 results in carbonyl loss and oxidative addition of the phosphorus-hydride, respectively the phosphorus-chloride, to the diiron centre yielding the iron(I) compounds [Fe 2(H)(μ-PPh 2)(CO) 5(μ-dppa) · THF ( 15 · THF) or [Fe 2(μ-Cl)(μ-PPh 2)(CO) 4(μ-dppa)] · THF ( 16 · THF). Electrophilic attac of NOBF 4 leads to cleavage of the diiron complex 6 · THF into [Fe(CO) 2(NO)dppa]BF 4 ( 17) and [Fe(CO) 3] without oxidation of the iron centres. In the solid state, compound 17 forms linear asv well as symmetrical bifureated H-bonds to the BF 4 anions. Furthermore, the NH group of 6 · THF can be deprotonated by n-BuLi. Treatment of 6 in its lithiated form with ClPPh 2 yields [Fe 2(μ-PPh 2)(μ-Ph 2P-N-PPh 2(CO) 0] ( 10) by simultaneous CO loss. The structures of 5, 6 · THF, 7b, 9 · 2 THF, 10, 15 · CHCl 3 and 17 were determined by X-ray crystallography. As the X-ray crystallography studies show, the PNP backbone of the coordinated ligand 1 is conformatively highly flexible. All the compounds were also characterized by 1H NMR, 13C( 1H) NMR, 31P( 1H) NMR, mass, and IR spectroscopy.