31P-NMR-Untersuchung an PhPH(CO)6Fe2(PPh)3Fe2(CO)6PPhH ? einem Vierkernkomplex mit einer ungewöhnlichen (PPh)3-Brücke

(CO)₆Fe₂(PhPH)₂ bildet mit PhPCl₂ den phosphidoverbrückten tetranuklearen Komplex [PhPHFe₂(CO)₆PPh]₂PPh. ³¹P{¹H}-NMR-Spektren der Titelverbindung werden als [AB]₂C-Systeme analysiert, Stereoisomere werden diskutiert. ³¹P-NMR Studies on PhPH(CO)₆Fe₂(PPh)₃Fe₂(CO)₆PPhH ? a Tetranuclear Complex with an Unusual (PPh)₃ Bridge (CO)₆Fe₂(PhPH)₂ and PhPCl₂ form [PhPHFe₂(CO)₆PPh]₂PPh, a tetranuclear complex with phosphido bridges. ³¹P{¹H}-NMR spectra are analysed as [AB]₂C systems, stereoisomers are discussed.     

Activation of CH bonds by transition metals I. Metallation of allylphosphines coordinated to iridium(I)

The reaction of the olefinic phosphines, R₂P(allyl) (R  t-butyl, cyclohexyl), with [(COT)₂IrCl]₂ (COT  cyclo-octene) in the presence of γ-picoline at room temperature yields the six coordinated, metallated complexes [(R₂PCH₂CH$\text{CH)I}$rHCl(R₂PCHCHCH₂)NC₆H₇]. In the case of (t-butyl)₂allylphosphine and without γ-picoline a five coordinated metallated compound is formed. The stereochemistries of the products were deduced from ¹H, ³¹P NMR and IR data.Reaction of [(COT)₂RhCl]₂ with the same phosphines yields an oily product, probably [(COT)RhClL₂] (L = phosphine) while [dibenzonitrileMCl₂] (M  Pd(II), Pt(II)) reacted with these phosphines to give L₂MCl₂.     

Reaktionen koordinierter Liganden. XVI. Struktur von Lithiumphosphido-Komplexen cis-Mo(CO)4(PRR′Li)2(R,R′  H,Alkyl, Aryl) in Lösung – eine 31P- und 7Li-NMR-spektroskopische Studie

Reactions of Coordinated Ligands. XVI. Structure of the Lithiumphosphido Complexes cis-Mo(CO)₄(PRR′Li)₂ (R, R′ ? H, Alkyl, Aryl) in Solution – a ³¹P and ⁷Li N.M.R. Study Complexes of the lithiumorganophosphides cis-Mo(CO)₄(PRR′Li)₂ (R, R′ ? H, Alkyl, Aryl) may be assigned to a ionic type (solvated) of structure [cis-Mo(CO)₄(PRR′)₂Li]^?Li⁺ in solution. According to ⁷Li and ³¹P NMR measurements at low temperatures the anion comprises a four membered MoP₂Li ring system. The temperature dependence of the ⁷Li and ³¹P NMR spectra may be explained by an intermolecular Li exchange and inversion of configuration at the phosphorus atoms.     

Activation of CH bonds by transition metals : V. A study of the mechanism of metallation reactions of benzyl- and meta-fluorobenzylphosphines with RhI,IrI, PdII and PtII compounds

Reaction of R₂PCH₂C₆H₅ (R = cyclohexyl or t-butyl) with [(COT)₂RhCl]₂, [(COT)₂IrCl]₂, PdCl₂ or PtCl₂(benzonitrile)₂ yields cyclometallated compounds. The reactivity appears to decrease in the order Ir^I ρ Rh^I ρ ρ Pd^II ≈ Pt^II, suggesting a different reaction mechanism for univalent and bivalent d⁸ metal atoms. Reaction of meta-FC₆H₄CH₂PR₂ with the same metal chlorides shows that for Rh^I and Ir^I a nucleophilic mechanism operates and for Pd^II an electrophilic one. For Pt^II no decision could be made on the basis of these experiments. Steric effects have a large influence on the rates of the reactions.     

PH-Functional Methylenebisphosphanes RR′P-CH2-PRH (R′= R,H) - Reactive Bridging Ligands with A Small Bite Angle

Abstract

PH-functional methylenbisphosphanes RR′P-CH₂-PRH (R′=R, H) are versatile ligands in coordination chemistry. They may oxidatively add with their PH-bonds to transition metals in low oxidation numbers and form cluster compounds with P-C-P-bridges. P-C-P-bond cleavage reactions afford phosphinidenes ?PR?(through a formal 1,2-hydrogen shift from phosphorus to the CH₂-group, RR′P-CH₂-PRH → RR′P-CH₃ + ?PR?) which are incorporated into the oligometallic cluster framework formed.     

Reaction of Methylene Bridged Diphosphines R2P-CH2-PRH AND RHP-CH2-PRH (R [dbnd] Me,Pri, But,CH2-Ph) with Transition Metal Carbonyls

Abstract

The PH-functional methylene bridged diphosphines R₂P-CH₂-PRH and RHP-CH₂-PHR have been synthesized using Cl₂P-CH₂-PCl₂ as a starting material. On reaction with Fe₂(CO)₉ oxidative addition and cleavage of the P-C-P-skeleton occur yielding cluster compounds, e. g. (CO)₉Fe₃(RR 'P-CH₂-PR)H (R [dbnd] Me, Prⁱ, Bu^t, CH₂-Ph, R' [dbnd] R or H) or (CO)₉Fe₃(μ₃PR)(μ₂PMeR)H.