Synthese,Struktur und Reaktivität von η3‐1,2‐Diphosphaallylkomplexen sowie von [{(η5‐C5H5)(CO)2W–Co(CO)3}{μ‐AsCH(SiMe3)2}(μ‐CO)]

Syntheses, Structure and Reactivity of η³‐1,2‐Diphosphaallyl Complexes and [{(η⁵‐C₅H₅)(CO)₂W–Co(CO)₃}{μ‐AsCH(SiMe₃)₂}(μ‐CO)] Reaction of ClP=C(SiMe₂iPr)₂ ( 3 ) with Na[Mo(CO)₃(η⁵‐C₅H₅)] afforded the phosphavinylidene complex [(η⁵‐C₅H₅)(CO)₂Mo=P=C(SiMe₂iPr)₂] ( 4 ) which in situ was converted into the η¹‐1,2‐diphosphaallyl complex [η⁵‐(C₅H₅)(CO)₂Mo{η³‐tBuPPC(SiMe₂iPr)₂] ( 6 ) by treatment with the phosphaalkene tBuP=C(NMe₂)₂. The chloroarsanyl complexes [(η⁵‐C₅H₅)(CO)₃M–As(Cl)CH(SiMe₃)₂] [where M = Mo ( 9 ); M = W ( 10 )] resulted from the reaction of Na[M(CO)₃(η⁵‐C₅H₅)] (M = Mo, W) with Cl₂AsCH(SiMe₃)₂. The tungsten derivative 10 and Na[Co(CO)₄] underwent reaction to give the dinuclear μ‐arsinidene complex [(η⁵‐C₅H₅)(CO)₂W–Co(CO)₃{μ‐AsCH(SiMe₃)₂}(μ‐CO)] ( 11 ). Treatment of [(η⁵‐C₅H₅)(CO)₂Mo{η³‐tBuPPC(SiMe₃)₂}] ( 1 ) with an equimolar amount of ethereal HBF₄ gave rise to a 85/15 mixture of the saline complexes [(η⁵‐C₅H₅)(CO)₂Mo{η²‐tBu(H)P–P(F)CH(SiMe₃)₂}]BF₄ ( 18 ) and [Cp(CO)₂Mo{F₂PCH(SiMe₃)₂}(tBuPH₂)]BF₄ ( 19 ) by HF‐addition to the PC bond of the η³‐diphosphaallyl ligand and subsequent protonation ( 18 ) and/or scission of the PP bond by the acid ( 19 ). Consistently 19 was the sole product when 1 was allowed to react with an excess of ethereal HBF₄. The products 6 , 9 , 10 , 11 , 18 and 19 were characterized by means of spectroscopy (IR, ¹H‐, ¹³C{¹H}‐, ³¹P{¹H}‐NMR, MS). Moreover, the molecular structures of 6 , 11 and 18 were determined by X‐ray diffraction analysis.     

Addition des O'Donnell Reagenzes [Ph2C=NCHCO2Me]– an π-koordinierte,ungesättigte Kohlenwasserstoffe in [(C6H7)Fe(CO)3]+, [(C7H9)Fe(CO)3]+, [(C7H7)M(CO)3]+ (M = Cr,Mo) und [(C2H4)Re(CO)5]+. α-Aminosäuren mit metallorganischen Seitenketten

Metal Complexes of Biologically Important Ligands. CXVII [1] Addition of the O'Donnell Reagent [Ph₂C=NCHCO₂Me]^– to Coordinated, Unsaturated Hydrocarbons of [(C₆H₇)Fe(CO)₃]⁺, [C₇H₉Fe(CO)₃]⁺, [(C₇H₇)M(CO)₃]⁺ (M = Cr, Mo), and [(C₂H₄)Re(CO)₅]⁺. α-Amino Acids with Organometallic Side Chains The addition of [Ph₂C=NCHCO₂Me]^– to [(C₆H₇)Fe(CO)₃]⁺, [(C₇H₉)Fe(CO)₃]⁺, [(C₇H₇)M(CO)₃]⁺ (M = Cr, Mo) and [(C₂H₄)Re(CO)₅]⁺ gives derivatives of α-amino acids with organometallic side chains. The structure of [(η⁴-C₆H₇)CH(N=CPh₂)CO₂Me]Fe(CO)₃ was determined by X-ray diffraction. From the adduct of [Ph₂C=NCHCO₂Me]^– and [(C₇H₇)Mo(CO)₃]⁺ the Schiff base of a new unnatural α-amino acid, Ph₂C=NCH(C₇H₇)CO₂Me, was obtained.     

Diimido‐, Imido(oxo)‐, Dioxo‐ und Imido(alkyliden)‐Halbsandwich‐Verbindungen über selektive Hydrolyse und α—H‐Abstraktion an Organylkomplexen des sechswertigen Molybdäns und Wolframs

Diimido, Imido Oxo, Dioxo, and Imido Alkylidene Halfsandwich Compounds via Selective Hydrolysis and α—H Abstraction in Molybdenum(VI) and Tungsten(VI) Organyl Complexes Organometal imides [(η⁵‐C₅R₅)M(NR′)₂Ph] (M = Mo, W, R = H, Me, R′ = Mes, tBu) 4 — 8 can be prepared by reaction of halfsandwich complexes [(η⁵‐C₅R₅)M(NR′)₂Cl] with phenyl lithium in good yields. Starting from phenyl complexes 4 — 8 as well as from previously described methyl compounds [(η⁵‐C₅Me₅)M(NtBu)₂Me] (M = Mo, W), reactions with aqueous HCl lead to imido(oxo) methyl and phenyl complexes [(η⁵‐C₅Me₅)M(NtBu)(O)(R)] M = Mo, R = Me ( 9 ), Ph ( 10 ); M = W, R = Ph ( 11 ) and dioxo complexes [(η⁵‐C₅Me₅)M(O)₂(CH₃)] M = Mo ( 12 ), M = W ( 13 ). Hydrolysis of organometal imides with conservation of M‐C σ and π bonds is in fact an attractive synthetic alternative for the synthesis of organometal oxides with respect to known strategies based on the oxidative decarbonylation of low valent alkyl CO and NO complexes. In a similar manner, protolysis of [(η⁵‐C₅H₅)W(NtBu)₂(CH₃)] and [(η⁵‐C₅Me₅)Mo(NtBu)₂(CH₃)] by HCl gas leads to [(η⁵‐C₅H₅)W(NtBu)Cl₂(CH₃)] 14 und [(η⁵‐C₅Me₅)Mo(NtBu)Cl₂(CH₃)] 15 with conservation of the M‐C bonds. The inert character of the relatively non‐polar M‐C σ bonds with respect to protolysis offers a strategy for the synthesis of methyl chloro complexes not accessible by partial methylation of [(η⁵‐C₅R₅)M(NR′)Cl₃] with MeLi. As pure substances only trimethyl compounds [(η⁵‐C₅R₅)M(NtBu)(CH₃)₃] 16 ‐ 18 , M = Mo, W, R = H, Me, are isolated. Imido(benzylidene) complexes [(η⁵‐C₅Me₅)M(NtBu)(CHPh)(CH₂Ph)] M = Mo ( 19 ), W ( 20 ) are generated by alkylation of [(η⁵‐C₅Me₅)M(NtBu)Cl₃] with PhCH₂MgCl via α‐H abstraction. Based on nmr data a trend of decreasing donor capability of the ligands [NtBu]^2— > [O]^2— > [CHR]^2— ? 2 [CH₃]^— > 2 [Cl]^— emerges.     

Formation of 18e− and 16e− Acyl(η3‐cyclooctenyl)rhodium(III) Complexes in the Reaction of Cationic (Cycloocta‐1,5‐diene)rhodium(I) Compounds with 2‐(Diphenylphosphino)benzaldehyde

The reaction of cationic diolefinic rhodium(I) complexes with 2‐(diphenylphosphino)benzaldehyde (pCHO) was studied. [Rh(cod)₂]ClO₄ (cod=cycloocta‐1,5‐diene) reacted with pCHO to undergo the oxidative addition of one pCHO with (1,2,3‐η)cyclooct‐2‐en‐1‐yl (η³‐C₈H₁₃) formation, and the coordination of a second pCHO molecule as (phosphino‐κP)aldehyde‐κO(σ‐coordination) chelate to give the 18e⁻ acyl(allyl)rhodium(III) species [Rh(η³‐C₈H₁₃)(pCO)(pCHO)]ClO₄ (see 1 ). Complex 1 reacted with [Rh(cod)(PR₃)₂]ClO₄ (R=aryl) derivatives 3 – 6 to give stable pentacoordinated 16e⁻ acyl[(1,2,3‐η)‐cyclooct‐2‐en‐1‐yl]rhodium(III) species [Rh(η³‐C₈H₁₃)(pCO)(PR₃)]ClO₄ 7 – 10 . The (1,2,3‐η)‐cyclooct‐2‐en‐1‐yl complexes contain cis‐positioned P‐atoms and were fully characterized by NMR, and the molecular structure of 1 was determined by X‐ray crystal diffraction. The rhodium(III) complex 1 catalyzed the hydroformylation of hex‐1‐ene and produced 98% of aldehydes (n/iso=2.6).     

Mononuclear Complexes of Platinum Group Metals Containing η6‐ and η5‐Cyclic Π‐Perimeter Hydrocarbon and Pyridylpyrazolyl Derivatives: Syntheses and Structural Studies

Piano‐stool‐shaped platinum group metal compounds, stable in the solid state and in solution, which are based on 2‐(5‐phenyl‐1H‐pyrazol‐3‐yl)pyridine ( L ) with the formulas [(η⁶‐arene)Ru( L )Cl]PF₆ {arene = C₆H₆ ( 1 ), p‐cymene ( 2 ), and C₆Me₆, ( 3 )}, [(η⁶‐C₅Me₅)M( L )Cl]PF₆ {M = Rh ( 4 ), Ir ( 5 )}, and [(η⁵‐C₅H₅)Ru(PPh₃)( L )]PF₆ ( 6 ), [(η⁵‐C₅H₅)Os(PPh₃)( L )]PF₆ ( 7 ), [(η⁵‐C₅Me₅)Ru(PPh₃)( L )]PF₆ ( 8 ), and [(η⁵‐C₉H₇)Ru(PPh₃)( L )]PF₆ ( 9 ) were prepared by a general method and characterized by NMR and IR spectroscopy and mass spectrometry. The molecular structures of compounds 4 and 5 were established by single‐crystal X‐ray diffraction. In each compound the metal is connected to N1 and N11 in a k² manner.     

2, 4‐Dimethylpenta‐1, 3‐dien‐ und 2, 4‐Dimethylpentadienyl‐Komplexe des Rhodiums und Iridiums

2, 4‐Dimethylpenta‐1, 3‐diene and 2, 4‐Dimethylpentadienyl Complexes of Rhodium and Iridium The complexes [(η⁴‐C₇H₁₂)RhCl]₂ ( 1 ) (C₇H₁₂ = 2, 4‐dimethylpenta‐1, 3‐diene) and [(η⁴‐C₇H₁₂)₂IrCl] ( 2 ) were obtained by interaction of C₇H₁₂ with [(η²‐C₂H₄)₂RhCl]₂ and [(η²‐cyclooctene)₂IrCl]₂, respectively. The reaction of 1 or 2 with CpTl (Cp = η⁵‐C₅H₅) yields the compounds [CpM(η⁴‐C₇H₁₂)] ( 3a : M = Rh; 3b : M = Ir). The hydride abstraction at the pentadiene ligand of 3a , b with Ph₃CBF₄ proceeds differently depending on the solvent. In acetone or THF the “half‐open” metallocenium complexes [CpM(η⁵‐C₇H₁₁)]BF₄ ( 4a : M = Rh; 4b : M = Ir) are obtained exclusively. In dichloromethane mixtures are produced which additionally contain the species [(η⁵‐C₇H₁₁)M(η⁵‐C₅H₄CPh₃)]BF₄ ( 5a : M = Rh; 5b : M = Ir) formed by electrophilic substitution at the Cp ring, as well as the η³‐2, 4‐dimethylpentenyl compound [(η³‐C₇H₁₃)Rh{η⁵‐C₅H₃(CPh₃)₂}]BF₄ ( 6 ). By interaction of 2, 4‐dimethylpentadienyl potassium with 1 or 2 the complexes [(η⁴‐C₇H₁₂)M(η⁵‐C₇H₁₁)] ( 7a : M = Rh; 7b : M = Ir) are generated which show dynamic behaviour in solution; however, attempts to synthesize the “open” metallocenium cations [(η⁵‐C₇H₁₁)₂M]⁺ by hydride abstraction from 7a , b failed. The new compounds were characterized by elemental analysis and spectroscopically, 4b and 5a also by X‐ray structure analysis.     

Ansa‐Complexes of [Mn(η5‐C5H5)(η6‐C6H6)]: Preparation,Characterization, and Reactivity of [n]Manganoarenophanes (n=1, 2, 3)

We report the synthesis of [n]manganoarenophanes (n=1, 2) featuring boron, silicon, germanium, and tin as ansa‐bridging elements. Their preparation was achieved by salt‐elimination reactions of the dilithiated precursor [Mn(η⁵‐C₅H₄Li)(η⁶‐C₆H₅Li)]?pmdta (pmdta=N,N,N′,N′,N′′‐pentamethyldiethylenetriamine) with corresponding element dichlorides. Besides characterization by multinuclear NMR spectroscopy and elemental analysis, the identity of two single‐atom‐bridged derivatives, [Mn(η⁵‐C₅H₄)(η⁶‐C₆H₅)SntBu₂] and [Mn(η⁵‐C₅H₄)(η⁶‐C₆H₅)SiPh₂], could also be determined by X‐ray structural analysis. We investigated for the first time the reactivity of these ansa‐cyclopentadienyl–benzene manganese compounds. The reaction of the distannyl‐bridged complex [Mn(η⁵‐C₅H₄)(η⁶‐C₆H₅)Sn₂tBu₄] with elemental sulfur was shown to proceed through the expected oxidative addition of the Sn?Sn bond to give a triatomic ansa‐bridge. The investigation of the ring‐opening polymerization (ROP) capability of [Mn(η⁵‐C₅H₄)(η⁶‐C₆H₅)SntBu₂] with [Pt(PEt₃)₃] showed that an unexpected, unselective insertion into the C_ipso?Sn bonds of [Mn(η⁵‐C₅H₄)(η⁶‐C₆H₅)SntBu₂] had occurred.     

Der Dihydridoiridium(III)‐Komplex [IrH2Cl(PiPr3)2] als Molekülbaustein für unsymmetrische Rhodium–Iridiumund Iridium–Iridium‐Zweikernverbindungen

The Dihydridoiridium(III) Complex [IrH₂Cl(P i Pr₃)₂] as a Molecular Building Block for Unsymmetrical Binuclear Rhodium–Iridium and Iridium–Iridium Compounds The title compound [IrH₂Cl(PiPr₃)₂] ( 3 ) reacts with the chloro‐bridged dimers [RhCl(PiPr₃)₂]₂ ( 1 ) and [IrCl(C₈H₁₄)(PiPr₃)]₂ ( 5 ) by cleavage of the Cl‐bridges to give the unsymmetrical binuclear complexes 4 and 6 with Rh(μ‐Cl)₂Ir and Ir(μ‐Cl)₂Ir as the central building block. The reactions of 3 with the bis(cyclooctene) and (1,5‐cyclooctadiene) compounds [MCl(C₈H₁₄)₂]₂ ( 7 , 8 ) and [MCl(η⁴‐C₈H₁₂)]₂ ( 9 , 10 ) (M = Rh, Ir) occur analogously and afford the rhodium(I)‐iridium(III) and iridium(I)‐iridium(III) complexes 11 – 14 in 70–80% yield. Treatment of [(η⁴‐C₈H₁₂)M(μ‐Cl)₂IrH₂(PiPr₃)₂] ( 13 , 14 ) with phenylacetylene leads to the formation of the substitution products [(η⁴‐C₈H₁₂)M(μ‐Cl)₂IrH(C≡CPh)(PiPr₃)₂] ( 15 , 16 ) without changing the central molecular core. Similarly, the compound [(η⁴‐C₈H₁₂)Rh(μ‐Br)₂IrH(C≡CPh)(PiPr₃)₂] ( 18 ) has been prepared; it was characterized by X‐ray crystallography.     

Synthese,Struktur und Reaktivität von η1und η3‐Allyl‐Rhenium‐Carbonylen

Synthesis, Structure, and Reactivity of η¹‐ and η³‐Allyl Rhenium Carbonyls In (η³‐C₃H₅)Re(CO)₄ one CO ligand can be substituted by PPh₃, pyridine, isocyanide and benzonitrile. With 1,2‐bis(diphenylphosphino)ethylene, 1,1′‐bis(diphenylphosphino)ferrocene and 1,2‐bis(4‐pyridyl)ethane dinuclear ligand bridged complexes are obtained. The η³‐η¹ conversion of the allyl ligand occurs on reaction of (η³‐C₃H₅)Re(CO)₄ with the bidendate ligands 1,2‐bis(diphenylphosphino)ethane and 1,3‐bis(diphenylphosphino)propane and with 2,2′‐bipyridine (L–L) which gives the complexes (η¹‐C₃H₅)Re(CO)₃(L–L). By reaction of (η³‐C₃H₅)Re(CO)₄ with bis(diphenylphosphino)methane the allyl group is protonated and under elemination of propene the complex (OC)₃Re(Ph₂PCHPPh₂)(η¹‐Ph₂PCH₂PPh₂) ( 19 ) with a diphosphinomethanide ligand is formed. On heating solutions of (η³‐C₃H₅)Re(CO)₄ and (η³‐C₃H₅)Re(CO)₃(CN‐2,5‐Me₂C₆H₃) ( 5 ) in methanol the methoxy bridged compounds Re₄(CO)₁₂(OH)(OMe)₃ and Re₂(CO)₄(CN‐2,5‐Me₂C₆H₃)₄(μ‐OMe)₂ ( 20 ) were isolated. The crystal structures of (η³‐C₃H₅)Re(CO)₃(CNCH₂SiMe₃) ( 4 ), [(η³‐C₃H₅)(OC)₃Re]₂‐ (μ‐bis‐(diphenylphosphino)ferrocene) ( 8 ), (η¹‐C₃H₅)Re(CO)₃‐ (bpy) ( 14 ), of 19 , 20 and of (OC)₃Re‐[Ph₂P(CH₂)₃PPh₂]Cl ( 16 ) were determined by X‐ray diffraction.     

Halfsandwich Carbonylmetal Complexes of Vanadium,Chromium, and Manganese Containing Tri(1‐cyclohepta‐2, 4, 6‐trienyl)phosphane,P(C7H7)3

The photo‐induced substitution of a CO ligand has been used to prepare the halfsandwich complexes (η³‐C₃H₅)V(CO)₄[P(C₇H₇)₃] ( 1 ), (η⁵‐C₅H₅)V(CO)₃[P(C₇H₇)₃] ( 2 ), (η⁷‐C₇H₇)V(CO)₂[P(C₇H₇)₃] ( 3 ), (η⁶‐C₆H₃Me₃)Cr(CO)₂[P(C₇H₇)₃] ( 4 ), and (η⁵‐C₅H₅)Mn(CO)₂[P(C₇H₇)₃] ( 7 ), in which the olefinic phosphane is coordinated as a conventional two‐electron ligand through the lone pair of electrons at phosphorus. Some analogues, which are permethylated at the aromatic ring ( 2* , 4* , 7* ), were included for comparison. Subsequent photo‐elimination of another CO group from 4 or 7 converts the olefinic phosphane into a chelating four‐electron ligand, leading to (η⁶‐C₆H₃Me₃)Cr(CO)[P(C₇H₇)₂(η²‐C₇H₇)] ( 5 ) and (η⁵‐C₅H₅)Mn(CO)[P(C₇H₇)₂(η²‐C₇H₇)] ( 8 ), respectively. The η²‐coordinated double bond in 5 and 8 can be displaced by trimethylphosphite to give (η⁶‐C₆H₃Me₃)Cr(CO)[P(C₇H₇)₃][P(OMe)₃] ( 6 ) and (η⁵‐C₅H₅)Mn(CO)[P(C₇H₇)₃][P(OMe)₃] ( 9 ). The ³¹P and ¹³C NMR spectra of all complexes are discussed, and X‐ray structure analyses for 2 and 8 are presented. Prolonged irradiation of 7 and 8 led to a di(cycloheptatrienyl)phosphido‐bridged dimer, {(η⁵‐C₅H₅)Mn(CO)[P(C₇H₇)₂]}₂( 10 ).     

Chirale Halbsandwich‐Pentamethylcyclopentadienyl‐Rhodium(III)‐ und Iridium(III)‐Komplexe mit Schiff‐Basen aus Salicylaldehyd und α‐Aminosäureestern [1]

Chiral Half‐sandwich Pentamethylcyclopentadienyl Rhodium(III) and Iridium(III) Complexes with Schiff Bases from Salicylaldehyde and α‐Amino Acid Esters [1] A series of diastereoisomeric half‐sandwich complexes with Schiff bases from salicylaldehyde and L‐α‐amino acid esters including chiral metal atoms, [(η⁵‐C₅H₅)(Cl)M(N,O‐Schiff base)], has been obtained from chloro bridged complexes [(η⁵‐C₅Me₅)(Cl)M(μ‐Cl)]₂ (M = Rh, Ir). Abstraction of chloride from these complexes with Ag[BF₄] or Ag[SO₃CF₃] affords the highly sensitive compounds [(η⁵‐C₅Me₅)M(N,O‐Schiff base]⁺X^? (M = Rh, Ir; X = BF₄, CF₃SO₃) to which PPh₃ can be added under formation of [(η⁵‐C₅Me₅)M(PPh₃)(N,O‐Schiff base)]⁺X^?. The diastereoisomeric ratio of the complexes ( 1 ‐ 7 and 11 ‐ 12 ) has been determined from NMR spectra.     

Molecular Structures of Mononuclear Rhodium Complexes Containing the Polydentate Ligand Tri(1‐cyclohepta‐2,4,6‐trienyl)phosphane,P(C7H7)3. Classification according to the 31P Chemical Shifts

The olefinic phosphane P(C₇H₇)₃ ( 5 ) behaves as a tetradentate tripod ligand in [RhCl{P(η²‐C₇H₇)₃}] ( 6 ), using all 3 cyclohepta‐2,4,6‐trienyl substituents as η²‐coordinating side‐arms. Nucleophilic displacement of the one‐electron chloro ligand by halides or pseudohalides to give [RhX{P(η²‐C₇H₇)₃}] (X = Br ( 7a ), I ( 7b ), N₃ ( 7c ), NCO ( 7d )) leaves the basket‐like framework [Rh{P(η²‐C₇H₇)₃}] intact. Reactions of 6 with three‐electron ligands result in decomplexation of one cyclohepta‐2,4,6‐trienyl ring and formation of [Rh(L³){P(C₇H₇)(η²‐C₇H₇)₂}] (L³ = acetylacetonate ( 8 ), 2‐carboethoxy cyclopentanonate ( 8a )), reactions of 6 with five‐electron ligands such as η⁵‐C₅H₅ cause decomplexation of two olefinic side‐arms to give [Rh(L⁵){P(C₇H₇)₂(η²‐C₇H₇)}] (L⁵ = η⁵‐C₅H₅ (Cp) ( 9 ), η⁵‐C₅H₄^tBu ( 9a )). The last remaining chelate ring in 9 is opened by pressure‐carbonylation to give the adduct [Rh(Cp)(CO){P(C₇H₇)₃}] ( 10 ) or by oxidative addition of halogens to form [Rh(Cp)X₂{P(C₇H₇)₃}] (X = Br, I). The full set of ¹H, ¹³C, ³¹P, and ¹⁰³Rh NMR data is given for the prototype complexes 7a , 8 , 9 , and 10 , and the molecular geometries of the [Rh{P(C₇H₇)₃}] fragments are compared on the basis of the X‐ray structural determinations of 6 , 8 , 8a , 9 , 9a , and 10 . The chemical shifts δ(³¹P) provide a reliable parameter for the prediction of the molecular structures of the rhodium complexes in solution.     

Reactivity Studies of η5‐ Indenyl and η5‐Cp* Ruthenium(II) Complexes towards some Polypyridyl Ligands

The reaction of [(η⁵‐L³)Ru(PPh₃)₂Cl], where; L³ = C₉H₇ ( 1 ), C₅Me₅ (Cp*) ( 2 ) with acetonitrile in the presence of [NH₄][PF₆] yielded cationic complexes [(η⁵‐L³)Ru(PPh₃)₂(CH₃CN)][PF₆]; L³= C₉H₇ ([3]PF₆) and L³ = C₅Me₅ ([4]PF₆), respectively. Complexes [3]PF₆ and [4]PF₆ reacts with some polypyridyl ligands viz, 2,3‐bis (α‐pyridyl) pyrazine (bpp), 2,3‐bis (α‐pyridyl) quinoxaline (bpq) yielding the complexes of the formulation [(η⁵‐L³)Ru(PPh₃)(L²)]PF₆ where; L³ = C₉H₇, L² = bpp, ([5]PF₆), L³ = C₉H₇, L² = bpq, ([6]PF₆); L³ = C₅Me₅, L² = bpp, ([7]PF₆) and bpq, ([8]PF₆), respectively. However reaction of [(η⁵‐C₉H₇)Ru(PPh₃)₂(CH₃CN)][PF₆] ([3]PF₆) with the sterically demanding polypyridyl ligands, viz. 2,4,6‐tris(2‐pyridyl)‐1,3,5‐triazine (tptz) or tetra‐2‐pyridyl‐1,4‐pyrazine (tppz) leads to the formation of unexpected complexes [Ru(PPh₃)₂(L²)(CH₃CN)][PF₆]₂; L² = tppz ([9](PF₆)₂), tptz ([11](PF₆)₂) and [Ru(PPh₃)₂(L²)Cl][PF₆]; L² = tppz ([10]PF₆), tptz ([12]PF₆). The complexes were isolated as their hexafluorophosphate salts. They have been characterized on the basis of micro analytical and spectroscopic data. The crystal structures of the representative complexes were established by X‐ray crystallography.     

Synthese und Struktur von η1‐Phosphaallyl‐, η1‐Arsaallylund η1‐Stibaallyleisen‐Komplexen [(η5‐C5Me5)(CO)2Fe–E(SiMe3)C(OSiMe3)=CPh2] (E = P,As, Sb)

Syntheses and Structures of η¹‐Phosphaallyl, η¹‐Arsaallyl, and η¹‐Stibaallyl Iron Complexes [(η⁵‐C₅Me₅)(CO)₂Fe–E(SiMe₃)C(OSiMe₃)=CPh₂] (E = P, As, Sb) The reaction of equimolar amounts of [(η⁵‐C₅Me₅)(CO)₂Fe–E(SiMe₃)₂] ( 1 a : E = P; 1 b : As; 1 c : Sb) and diphenylketene afforded the η¹‐phosphaallyl‐, η¹‐arsaallyl‐, and η¹‐stibaallyl complexes [(η⁵‐C₅Me₅)(CO)₂Fe–E(SiMe₃)C(OSiMe₃)=CPh₂] ( 2 a : E = P; 2 b : As; 2 c : Sb). The molecular structures of 2 b and 2 c were elucidated by single crystal X‐ray analyses.     

Stereoselectivity in Diphos Addition to Molybdenum Complex with Pyridine‐2‐thionate (pyS) and η3‐Methallyl Coordinated Ligands

The conformational isomers endo‐ and exo‐[Mo{η³‐C₃H₄(CH₃)}(η²‐pyS)(CO)(η²‐diphos)] (diphos: dppm = {bis(diphenylphosphino)methane}, 2 ; dppe = {1,2‐bis(diphenylphosphino)ethane}, 3 ) are prepared by reacting the double‐bridged pyridine‐2‐thionate (pyS) complex [Mo{η³‐C₃H₄(CH₃)}(CO)₂]₂(η¹:η²:μ‐pyS)₂, 1 with diphos in refluxing acetonitrile. Stereoselectivity of the methallyl, C₃H₄(CH₃), ligand improves the formation of the exo‐conformation of 2 and 3 . Orientations and spectroscopy of these complexes are discussed.     

Cyclic Tribismuthide as a Piano Stool Complex Ligand – Synthesis and Crystal Structure of (η3‐Bi3)M(CO)33– (M = Cr,Mo)

The reactions between K₅Bi₄, [(C₆H₆)Cr(CO)₃] or [(C₇H₈)Mo(CO)₃], and [2.2.2]crypt in liquid ammonia yielded the compounds [K([2.2.2]crypt)]₃(η³‐Bi₃)M(CO)₃ · 10NH₃ (M = Cr, Mo), which crystallize isostructurally in P2₁/n. Both contain an 18 valence electron piano‐stool complex with a η³‐coordinated Bi₃‐ring ligand. The Bi–Bi distances range from 2.9560(5) to 2.9867(3) Å and are slightly shorter than known Bi–Bi single bonds but longer than Bi–Bi double bonds. The newly found compounds complete the family of similar complexes with E₃‐ring ligands (E = P‐Bi).     

Zur Reaktivität der Ferriophosphaalkene [(η5‐C5Me5)(CO)2FeP=C(NR)R2] (NR = NMe2, NC5H10, R2 = Ph,tBu) gegenüber Protonsäuren,Alkylierungsmitteln und [{(Z)‐Cycloocten}Cr(CO)5]

Transition Metal‐substituted Phosphaalkenes. 42 Reactivity of the Ferriophosphaalkenes [(η⁵‐C₅Me₅)(CO)₂FeP=C(NR )R²] (NR = NMe₂, NC₅H₁₀, R² = Ph, t Bu) towards Protic Acids, Alkylation Reagents, and [{( Z )‐Cyclooctene}Cr(CO)₅] The reaction of equimolar amounts of [(η⁵‐C₅Me₅)(CO)₂FeP=C(NR )R²] ( 2 a : NR = NMe₂, R² = Ph; 2 b : NMe₂. tBu; 2 c : NC₅H₁₀, Ph) and etherial HBF₄ gave rise to the formation of [(η⁵‐C₅Me₅)(CO)₂FeP(H)C(NR )R²] (BF₄) ( 3 a – c ) which were isolated as light red powders. Compounds 2 a – c were converted into [(η⁵‐C₅Me₅)(CO)₂FeP(Me)C(NR )R²] (SO₃CF₃) ( 4 a – c ) by treatment with methyl trifluoromethane sulfonate. In addition 2 a and Me₃SiCH₂OSO₂CF₃ afforded light red [(η⁵‐C₅Me₅)(CO)₂FeP(CH₂SiMe₃)C(NMe₂)Ph](SO₃CF₃) ( 5 ). The black complex [(η⁵‐C₅Me₅)(CO)₂FeP{Cr(CO)₅}C(NMe₂)Ph] ( 6 ) resulted from the combination of 2 a with [{(Z)‐cyclooctene}Cr(CO)₅]. The novel products were characterized by elemental analyses and spectra (IR, ¹H‐, ¹³C‐ und ³¹P‐NMR).     

Heterobimetallische phosphanido-verbrückte Zweikern-Komplexe - Synthese von cis-rac-[(η-C5H4R)2Zr{μ-PH(2,4,6−iPr3C6H2)}2M(CO)4] (RMe,MCr,Mo; RH,MMo)

Heterobimetallic Phosphanido-bridged Dinuclear Complexes - Syntheses of cis-rac-[(η-C₅H₄R)₂Zr{μ-PH(2,4,6-ⁱPr₃C₆H₂)}₂M(CO)₄] (R?Me, M?Cr, Mo; R?H, M?Mo) The zirconocene bisphosphanido complexes [(η-C₅H₄R)₂Zr{PH(2,4,6-ⁱPr₃C₆H₂)}₂] (R?Me, H) react with [(NBD)M(CO)₄] (NBD?norbornadiene, M?Cr, Mo) to give only one diastereomer of the phosphanido-bridged heterobimetallic dinuclear complexes cis-rac-[(η-C₅H₄R)₂Zr{μ-PH(2,4,6-ⁱPr₃C₆H₂)}₂M(CO)₄] [R?Me, M?Cr ( 1 ), Mo ( 2 ); R?H, M?Mo ( 3 )]. However, no reaction was observed between [(η-C₅H₅)₂Zr{PH(2,4,6-^tBu₃ C₆H₂)}₂] and [Pt(PPh₃)₄]. 1—3 were characterised spectroscopically. For 1—3 , the presence of the racemic isomer was shown by NMR spectroscopy. No reaction was observed at room temperature for 3 and CS₂, (NO)BF₄, Me₃NO or PH(2,4,6-Me₃C₆H₂)₂. With Et₂AlH or PhC?CH decomposition of 3 was observed.     

Reaction of (η5‐C5H5)Fe(CO)2I with Anionic Bidentate Phosphine Ligands PPh2(o‐C6H4NHLi) or PPh2(o‐C6H4OLi)

The o‐substituted hybrid phenylphosphines, PPh₂(o‐C₆H₄NH₂) and PPh₂(o‐C₆H₄OH), could be deprotonated with LDA or n‐BuLi to yield PPh₂(o‐C₆H₄NHLi) and PPh₂(o‐C₆H₄OLi), respectively. When added to a solution of (η⁵‐C₅H₅)Fe(CO)₂I at room temperature, these two lithiated reagents produce a chelated neutral complex 1 (η⁵‐C₅H₅)Fe(CO)[C(O)NH(o‐C₆H₄)PPh₂‐C,P‐η²] for the former and mainly a zwitterionic complex 2 , (η⁵‐C₅H₅)Fe⁺(CO)₂[PPh₂(o‐C₆H₄O^?)] for the latter. Complex 1 could easily be protonated and then decarbonylated to give 4 [(η⁵‐C₅H₅)Fe(CO){NH₂(o‐C₆H₄)PPh₂‐N,P‐η²}⁺]. Complexes 1 and 4‐I have been crystallographically characterized with X‐ray diffraction.     

Azido­[1,1′‐bis­(di­phenyl­phosphino)­ferrocene](penta­methyl­cyclo­penta­dienyl)­rhodium(III) hexa­fluoro­phosphate

In the title compound, azido‐2κN‐bis­[μ‐(1η⁵:2κP)‐di­phenyl­phosphino­cyclo­penta­dienyl][2(η⁵)‐penta­methyl­cyclo­penta­di­enyl]­iron(III)­rhodium(III) hexa­fluoro­phosphate, [{Rh(C₁₀H₁₅)(N₃)}{Fe(μ‐C₁₇H₁₄P)₂}]PF₆ or [FeRh(C₁₀H₁₅)(μ‐C₁₇H₁₄P)₂(N₃)]PF₆, the coordination sphere of Rh^III can be described as pseudo‐tetrahedral, composed of two P atoms from a 1,1′‐bis­(di­phenyl­phosphino)­ferrocene (dppf) ligand, an azido N atom and the centroid of the ring of a C₅Me₅ (Cp*) ligand. The two cyclo­penta­dienyl rings in the dppf moiety adopt an eclipsed conformation. The Rh⋯Fe distance is 4.340 (2) Å.