Reactions of phosphorus fluorides and ortho-carborane ditertiary aminophosphines

Fluorophosphine bidentate ligands containing o-carborane as backbone can be prepared by the reaction of the lithium-o-carboranes and PF₂X derivatives to give only two species: the unsymmetrical (C₆H₅)₂P[B₁₀H₁₀C₂]PF₂ and the cyclic FP[B₁₀H₁₀C₂]₂PF, both in low yield. However, exchange of F and NMe₂ groups by use of PF₅ or PF₃ provides a facile way to produce several new fluorophosphines.Phosphorus pentafluoride forms solid adducts with the o-phosphino derivatives (C₆H₅)₂P[B₁₀H₁₀C₂]P(NMe₂)₂, (Me₂N)₂P[B₁₀H₁₀C₂]P(NMe₂)₂ and (C₆H₅)₂P[B₁₀H₁₀C₂]H. All the adducts contain a phosphorus-phosphorus bond as evidenced from i.r., NMR and stoichiometry. The stability of the adducts reflects the strength of the PP bond formed upon complexation. When suspensions or solutions of the adducts are heated they exchange F and NMe₂ groups and no redox occurs. The products (C₆H₅)₂P[B₁₀H₁₀C₂]P(F)NMe₂(I) and Me₂N(F)P[B₁₀H₁₀C₂]P(F)NMe₂(II) react further with PF₅ giving (C₆H₅)₂P[B₁₀H₁₀C₂]PF₂(III) and F₂P[B₁₀H₁₀C₂]PF₂(IV).The precursors also react with phosphorus trifluoride to produce only (I) and (Me₂N)₂P[B₁₀H₁₀C₂]P(F)NMe₂(V) regardless of the reaction conditions. All the products I–V have been identified by ¹H, ¹⁹F, and ³¹P NMR and i.r. spectroscopy, mass spectrometry, and elemental analysis. The NMR spectra of the novel (IV) have been analysed as X₂AA¹X¹₂ spin system.     

Reaction of PF5·CH3CN with sulfide

Nitriles react with PF₅ and also with AsF₅, SbF₅ forming 1:1-adducts. Using C₂Cl₃F₃ as a solvent is of advantage for this reaction. PF₅·CH₃CN and [N(C₂H₅)₄]SH give [N(C₂H₅)₄][P₂S₂F₈] with a sulfur double bridge and hexafluorophosphate in acetonitrile [1]. In case of AsF₅·CH₃CN a salt with the anion [AsF₅NHCSCH₃]^? has been isolated [2]. Following products have been confirmed in a reaction mixture of PF₅·CH₃CN and SH^? in acetonitrile by NMR (³¹P and ¹⁹F): [PF₆]^?, [F₅PSPF₅]^2?,

, F₄PSH, F₃PS, HPS₂F₂, [PS₂F₂]^?, [F₅PNC(SH)CH₃]^?, [F₅PNHCSCH₃]^?, [F₅PSH]^?. With a ratio PF₅·CH₃CN: SH^? = 2:1 the S-bridge-complexes are prefered whereas in case of a ratio 1:1 the non-bridged P-complexes are the main products.     

Preparation and properties of some cationic binuclear platinum(I) complexes

Reaction of [Pt₂Cl₂(μ-dppm)₂] with ligands, L, in the presence of [PF₆^- gave stable cationic diplatinum(I) complexes [Pt₂L₂(μ-dppm)₂][PF₆]₂ where L = PMe₂Ph, PMePh₂, PPh₃, NH₃, C₅H₅N. Reaction of [Pt₂(NH₃)₂(μ-dppm)₂][PF₆]₂ with CO gave [Pt₂(CO)₂(μ-dppm)₂][PF₆]₂ and an unsymmetrical complex [Pt₂(CO)(C₅H₅N)(μ-dppm)₂][PF₆]₂ was also prepared. The compounds were characterized by vibrational and ¹H and ³¹P NMR spectroscopy and the presence of direct platinumplatinum bonds is indicated.     

Ethylen(hydrido)-metallkomplexe aus M(CH2)CH3-vorstufen: modellreaktionen für einen elementarschritt der fischer-tropsch-synthese

The compounds C₆Me₆Ru(Ch₃)₂, C₆H₆Os(CH₃)₂PMe₃ and C₅H₅Ir(CH₃)₂-Pprⁱ₃ react with [CPh₃]PF₆ in Ch₂Cl₂ to give the ethylene(hydrido)metal complexes [C₆Me₆RuH(C₂H₄)PR₃]PF₆, [C₆H₆OsH(C₂H₄)PMe₃]PF₆ and [C₅H₅IrH(C₂H₄)PPrⁱ₃]PF₆, respectively. Treatment of C₆Me₆RuCH₃(C1)PMe₃ with [CPh₃]PF₆ leads to cleavage of the RuCH₆ bond instead of hydride elimination; in the presence of PMe₂Ph the compound [C₆Me₆RuCl(PMe₂Ph)PMe₃]PF₆ is obtained. The reaction of C₅H₅RhCH₂OMe(PMe₃)CH₃ with HBF₄ gives [C₅H₅RhH(C₂H₄)PMe₃]BF₄ and methanol. It is assumed that the formation of the ethylene(hydrido)metal complexes always occur via a M(CH₂)CH₃ intermediate, radical intermediates not being observed. The crystal structure of [C₆Me₆RuH(C₂H₄)PPh₃]PF₆ has been determined. The cation of 1.50 Å. The CC distance in the ethylene ligand is 1.41(1) Å and thus is significantly longer than in the free olefin.     

Homo‐ and Heterodinuclear Ir and Rh Imine‐functionalized Protic NHC Complexes: Synthetic,Structural Studies,and Tautomerization/Metallotropism Insights

The influence of the potentially chelating imino group of imine‐functionalized Ir and Rh imidazole complexes on the formation of functionalized protic N‐heterocyclic carbene (pNHC) complexes by tautomerization/metallotropism sequences was investigated. Chloride abstraction in [Ir(cod)Cl{C₃H₃N₂(DippN=CMe)‐κN3}] ( 1 a ) (cod=1,5‐cyclooctadiene, Dipp=2,6‐diisopropylphenyl) with TlPF₆ gave [Ir(cod){C₃H₃N₂(DippN=CMe)‐κ²(C2,N_imine)}]⁺[PF₆]^? ( 3 a ⁺[PF₆]^?). Plausible mechanisms for the tautomerization of complex 1 a to 3 a ⁺[PF₆]^? involving C2?H bond activation either in 1 a or in [Ir(cod){C₃H₃N₂(DippN=CMe)‐κN3}₂]⁺[PF₆]^? ( 6 a ⁺[PF₆]^?) were postulated. Addition of PR₃ to complex 3 a ⁺[PF₆]^? afforded the eighteen‐valence‐electron complexes [Ir(cod)(PR₃){C₃H₃N₂(DippN=CMe)‐κ²(C2,N_imine)}]⁺[PF₆]^? ( 7 a ⁺[PF₆]^? (R=Ph) and 7 b ⁺[PF₆]^? (R=Me)). In contrast to Ir, chloride abstraction from [Rh(cod)Cl{C₃H₃N₂(DippN=CMe)‐κN3}] ( 1 b ) at room temperature afforded [Rh(cod){C₃H₃N₂(DippN=CMe)‐κN3}₂]⁺[PF₆]^? ( 6 b ⁺[PF₆]^?) and [Rh(cod){C₃H₃N₂(DippN=CMe)‐κ²(C2,N_imine)}]⁺[PF₆]^? ( 3 b ⁺[PF₆]^?) (minor); the reaction yielded exclusively the latter product in toluene at 110 °C. Double metallation of the azole ring (at both the C2 and the N3 atom) was also achieved: [Ir₂(cod)₂Cl{μ‐C₃H₂N₂(DippN=CMe)‐κ²(C2,N_imine),κN3}] ( 10 ) and the heterodinuclear complex [IrRh(cod)₂Cl{μ‐C₃H₂N₂(DippN=CMe)‐κ²(C2,N_imine),κN3}] ( 12 ) were fully characterized. The structures of complexes 1 b , 3 b ⁺[PF₆]^?, 6 a ⁺[PF₆]^?, 7 a ⁺[PF₆]^?, [Ir(cod){C₃HN₂(DippN=CMe)(DippN=CH)(Me)‐κ²(N3,N_imine)}]⁺[PF₆]^? ( 9 ⁺[PF₆]^?), 10? Et₂O ? toluene, [Ir₂(CO)₄Cl{μ‐C₃H₂N₂(DippN=CMe)‐κ²(C2,N_imine),κN3}] ( 11 ), and 12? 2 THF were determined by X‐ray diffraction.     

Synthetic applications of the photolysis of the cyclopentadienyliron-(ρ-xylene) cation

Photolysis of CpFe(ρ-xylene)⁺ (Cp = η⁵-cyclopentadienyl) in the presence of suitable 6- or 2-electron donor ligands results in replacement of the aromatic ring with one 6-electron or three 2-electron donor ligands. The compounds [CPFe(η⁶-C₇H₈)]BF₄ (C₇H₈ = cycloheptatriene), [CpFe(η⁶-C₈H₈)]PF₆, (C₈H₈ = cyclooctatetraene), [CpFe(η⁶-PCP)]PF₆ (PCP = 2,2-paracyclophane), [CpFe-(P(OCH₃)₃)₃]PF₆ and [CpFe(P(OCH₂CH₃)₃)₃]PF₆ were prepared in this manner. The compound [CpFe(TM4)₃FeCp](PF₆)₂ · CH₃COCH₃ (TM4 = 2,5-dimethyl-2,5 diisocyanohexane) was prepared in two steps. First, [CpFe(ρ-xylene)]PF₆ was irradiated with an excess of the free TM4 ligand producing a mixture of [CpFe(TM4)₃]⁺ and [CpFe(TM4)₃FeCp]²⁺. An additional equivalent of [CpFe(p-xylene)]PF₆ was added to this mixture and photolysis yielded [CpFe(TM4)₃FeCp](PF₆)₂ · CH₃COCH₃.     

Metallkomplexe mit anionischen Liganden von Elementen der 4. Hauptgruppe. XI. Substitutionsreaktionen der Trichlorgermid- und Trichlorstannid-Ionen an Metalltrifluorphosphin-Komplexen

Metal Complexes with Anionic Ligands of Main Group IV Elements. XI. Substitution Reactions of Trichlorogermide and Trichlorostannide Ions with Metaltrifluorophosphine Complexes The photochemical reactions of [SnCl₃]^? in THF with the metal(0)-trifluorophosphine complexes of Ni, Fe, and Mo result in [Ni(PF₃)₃SnCl₃]^?, [Fe(PF₃)₃(SnCl₂]^?, and [Mo(PF₃)₅SnCl₃]^?. [GeCl₃]^?, in substitution reactions not as reactive as [SnCl₃]^?, does react under similar conditions with Fe(NO)₂(PF₃)₂ only, to yield [Fe(NO)₂(PF₃)GeCl₃]^?. With CpMn(PF₃)₃ (Cp = h⁵-C₅H₅) by the intermediatly formed CpMn(PF₃)₂THF both substitution derivatives [CpMn(PF₃)₂ECl₃]^? (E = Ge, Sn) are found. The metallate(0) complexes are isolated as [As(C₆H₅))₄]⁺- and [N(C₂H₅)₄]⁺ -salts; the i.r.- and ¹⁹F-n.m.r.-spectra are reported.     

Cyclopentadienyleisen-komplexe mit P(OR)3-liganden; Synthese und spektroskopische charakterisierung

Reactions of reactive cyclopentadienyliron complexes C₅H₅Fe(CO)₂I, [C₅H₅Fe(CO)₂THF]BF₄, [C₅H₅Fe(CO)((CH₃)₂S)₂]BF₄ and [C₅H₅Fe(p-(CH₃)₂C₆H₄)]PF₆ with P(OR)₃ as ligands (R = CH₃, C₂H₅, i-C₃H₇ and C₆H₅) lead to the formation of the complex compounds C₅H₅Fe(CO)_2?n(P(OR)₃)_nI and [C₅H₅Fe(CO)_3?n(P(OR)₃)_n]X (n = 1, 2 and n = 1–3, X = BF₄, PF₆). Spectroscopic investigations (IR, ¹H, ¹³C and ³¹P NMR) indicate an increase of electron density on the central metal with increasing substitution of CO groups by P(OR)₃ ligands. The stability of the compounds increase in the same way.     

Calorimetric studies on phase transitions arising from orientational order-disorder of the molecular axes of ferrocene and its derivatives

Heat capacities of the channel inclusion compound, Fe(C₅D₅)₂ · 3(NH₂)₂CS, and two ferrocenium salts, [Fe(C₅H₅)(C₆H₆)]⁺ (PF₆)⁻ and [Fe(C₅H₅)₂]⁺ (PF₆)⁻, have been measured with adiabatic calorimeters between 13 and 393 K. Five phase transitions were found for Fe(C₅D₅)₂ · 3(NH₂)₂CS corresponding to those for Fe(C₅H₅)₂ · 3(NH₂)₂CS. The dominant phase transitions at 145.8 and 160.6 K are responsible for the onset of reorientational order-disorder of the molecular axis of Fe(C₅D₅)₂ in the clathrate cavity. The mass-effect of the guest ferrocene molecule on the phase transitions was not remarkable. The ferrocenium salt, [Fe(C₅H₅)(C₆H₆]⁺(PF₆)⁻, exhibited four phase transitions and two glass transition phenomena at low temperatures while its analog, [Fe(C₅H₅)₂]⁺(PF₆)⁻, brought about only three phase transitions without showing the glass transition. The higher-temperature phase transitions in these two salts have been assigned to the reorientational order-disorder mechanism of the molecular axes of the cations in the pseudo-cavities formed by eight PF⁻₆ anions. For the origin of the lower-temperature phase transitions in these two salts, three possibilities have been discussed. Among them, plausible origin is likely to be an order-disorder change of PF⁻₆ anion in the lattice. An important unsettled problem common to these three compounds is a question whether or not the Fe(C₅D₅)₂ and the cations, [Fe(C₅H₅)(C₆H₆)]⁺ and [Fe(C₅H₅)₂]⁺, are still reorienting around their molecular axes even at the lowest-temperature phase.     

Pentamethylcyclopentadienyl ruthenium(II) complexes of para-substituted N-(pyrid-2-ylmethylene)-phenylamine ligands: syntheses,spectral and structural studies

The reaction of [(η⁵-C₅Me₅)Ru(PPh₃)₂Cl] (1) with acetonitrile in the presence of excess NH₄PF₆ leads to the formation of the cationic ruthenium(II) complex [(η⁵-C₅Me₅)Ru(PPh₃)₂(CH₃CN)]PF₆ (2). The complex (2) reacts with a series of N,N′ donor Schiff base ligands viz. para-substituted N-(pyrid-2-ylmethylene)-phenylamines (ppa) in methanol to yield pentamethylcylopentadienyl ruthenium(II) Schiff base complexes of the formulation [(η⁵-C₅Me₅)Ru(PPh₃)(C₅H₄N-2-CHN-C₆H₄-p-X)]PF₆ [3a]PF₆–[3f]PF₆, where C₅Me₅ = pentamethylcylopentadienyl, X = H, [3a]PF₆, Me, [3b]PF₆, OMe, [3c]PF₆, NO₂, [3d]PF₆, Cl, [3e]PF₆, COOH, [3f]PF₆. The complexes were isolated as their hexafluorophosphate salts. The complexes were fully characterized on the basis of elemental analyses and NMR spectroscopy. The molecular structure of a representative complex, [(η⁵-C₅Me₅)Ru(PPh₃)(C₅H₄N-2-CHN-C₆H₄-p-Cl)]PF₆ [3e]PF₆, has been established by X-ray crystallography.     

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.     

Photochemical reactions of cationic isocyanide/carbonyl complexes of iron with selected nucleophiles

Photolysis of (η⁵-C₅H₅Fe(CO)(CNMe)₂]PF₆ in the presence of excess nucleophiles resulted in efficient substitution of the carbonyl ligand, generating the new isocyanide complexes (η⁵-C₅H₅Fe(CNMe)₂)(L)]PF₆ (L = PPh₃, AsPh₃, SbPh₃, pyridine, acetonitrile, and ethylene). Similar reactions of (η⁵-C₅H₅Fe(CO)_2)(CNMe)PF₆ led to sequential replacement of both carbony groups with the exception of L  ethylene. No evidence of photochemical isocyanide substitution was found. The same carbonyl complexes failed to reach with L thermally. In the absence of light, ethylene, pyridine, and acetonitrile complexes were found to disporportionate in the manner [η⁵-C₅H₅Fe(CNMe)(L)₂]PF₆→ [η⁵C₅H₅Fe(CNMe)₂(L)]PF₆ → [η⁵-C₅H₅Fe(CNMe)₃]PF₆ with the first rearrangement occurring much faster than the second. The new isocyanide complexes are characterized by their infrared and NMR (¹H, ¹³C) spectra.     

Reactions of transition metal σ-acetylide complexes: IX. Preparation and properties of some cycloheptatrienylvinylidene complexes

Addition of [C₇H₇][PF₆] to iron, ruthenium or osmium alkynyl complexes has given eight cationic cycloheptatrienylvinylidene derivatives [M{C C(C₇H₇)R}(L)₂ (η-C₅H₅)][PF₆] (M = Fe, Ru or Os; R = Me, Pr, Ph or C₆F₅; L = PPh₃, L₂ = dppm or dppe; but not all combinations). With Fe(C₂Ph)(CO)₂(η-C₅H₅), only [Fe(CO)₂(thf)(η-C₅H₅)][PF₆] was obtained. Reactions of the new complexes are characterised by loss of the C₇H₇ group. The NMR spectra and FAB mass spectra are described in detail.     

The First [4+2]‐Coordinated Tetraorganolead Compound: Synthesis,Structure and Conversion into a Triorganolead Cation,a Benzoxaphosphaplumbole,and Diorganolead Dihalides

The syntheses and molecular structures, as determined by single‐crystal X‐ray diffraction analysis, of the first intramolecularly [4+2]‐coordinated tetraorganolead compound {4‐t‐Bu‐2, 6‐[P(O)(OEt)₂]₂C₆H₂}PbPh₃ ( 2 ) and the triphenyllead chloride adduct of the first intramolecularly coordinated benzoxaphosphaplumbole {[1(Pb), 3(P)‐Pb(Ph)₂OP(O)(OEt)‐5‐t‐Bu‐7‐P(O)(OEt)₂]C₆H₂·Ph₃PbCl} ( 3a ) are reported. The reaction of 2 with [Ph₃C]⁺ [PF₆]^— and p‐MeC₆H₄SO₃H, respectively, provides the triorganolead salts {4‐t‐Bu‐2, 6‐[P(O)(OEt)₂]₂C₆H₂}PbPh₂⁺X^— ( 4 , X = PF₆; 4a , X = p‐MeC₆H₄SO₃). Reaction of 2 with bromine and hydrogen chloride, respectively, gives the diorganolead dihalides {4‐t‐Bu‐2, 6‐[P(O)(OEt)₂]₂C₆H₂}PbPhX₂ ( 5 , X = Br; 6 , X = Cl).     

A heteronuclear compound of ruthenium and silver containing bridging tris(pyridyl)methanoate ligands

The reaction of [{Ru(η⁶-C₆H₆)Cl(μ-Cl)}₂] with Py₃COH in ethanol results in the formation of the cation [Ru(η⁶-C₆H₆)(N,N′,O,-(C₅H₄N)₃CO)]⁺ which is isolated as its hexafluorphosphate salt 1. The cation acts as a ligand towards other transition metal ions. With Ag⁺ the hetero-trinuclear complex [{Ru(η⁶-C₆H₆)((C₅H₄N)₃CO)}₂Ag][PF₆]₃ 2 is formed, while reaction with [Pd(PhCN)₂Cl₂] gives the bimetallic [Ru(η⁶-C₆H₆)((C₅H₄N)₃CO)PdCl₂][PF₆] 3. Both compounds were fully characterised by spectroscopic methods and the trinuclear complex was additionally characterised by X-ray diffraction.     

Ligating properties of thionitrosoamines: IV. Cationic complexes of rhodium(I), rhodium(III), and ruthenium(II) containing N-thionitrosodimethylamine

The solvento species obtained by treatment of the complexes [Rh(1,5-cyclooctadiene)Cl]₂, [Rh(norbornadiene)Cl]₂, [Rh(CO)₂Cl]₂, C₅H₅Rh(CO)I₂, [C₅Me₅RhCl₂]₂, and [Ru(C₆H₆)Cl₂]₂ with AgPF₆ in acetone or acetonitrile react with a large excess of Me₂NNS to give the compounds [Rh(1,5-C₈H₁₂)-(SNNMe₂)₂]PF₆ (1a), [Rh(C₇H₈)(SNNMe₂)₂]PF₆ (1b), [Rh(CO)₂(SNNMe₂)₂]PF₆ (2), [C₅H₅Rh(SNNMe₂)₃](PF₆)₂ (3), [C₅Me₅Rh(SNNMe₂)₃](PF₆)₂ (4), and [Ru(C₆H₆(SNNMe₂)₃](PF₆) (5). If the thionitroso ligand is not preent in large excess decomposition often occurs. The use of AgClO₄ allows isolation of the perchlorate salts of 1a, 1b, 2, 4, and 5, and the complexes [C₅H₅Rh-(SNNMe₂)₂(ClO₄)ClO₄ (6) and Rh(1,5-C₈H₁₂)(SNNMe₂)(ClO₄) (7). In the H¹ NMR spectra the methyl protons of Me₂NNS are observed as two quadruplets, in the range δ 3.75–4.25 (⁴J(HH) ca. 0.7 Hz) because of restricted rotation around the NN bond. The rhodium(I) complexes (1a, 1b, and 2) reacts with PPh₃ or p-tolylPPh₂ to give labile products, and only [Rh(1,5-C₈H₁₂)(SNNMe₂)(PPh₃)]ClO₄ (8) and [Rh(1,5-C₈H₁₂)(SNNMe₂)(p-tolylPPh₂)]ClO₄ (9) were isolated and characterized.     

Preparation and properties of new ferrocenyl heterobimetallic complexes with counterion dependent NLO responses

New ferrocenyl-based bimetallic cationic compounds of the type of (E)-[CpFe(η⁵-C₅H₄)(CHCH)(C₆H₄)CNRuCp(PPh₃)₂]X (X=PF₆, BF₄) and of (E)-[CpFe(η⁵-C₅H₄)(CHCH)(C₆H₄)CNFeCp(CO)₂]PF₆ have been obtained and characterized. The crystal structure of (E)-[CpFe(η⁵-C₅H₄)(CHCH)(C₆H₄)CNRuCp(PPh₃)₂]BF₄ has been established by means of X-ray diffractometry. The NLO responses of the compounds have been studied by the hyper-Rayleigh scattering technique and the hyperpolarizability is found to be dependent on the nature of the counterion.     

A 13C-NMR. Study of naphthalene chromium complexes. Correlation with reactivity: Nucleophilic aromatic substitution reactions

The ¹³C-NMR. spectra of the series of complexes η⁶-naphthalene · CrL₃ (L? CO ( 1 ), PF₃ ( 2 ), PF₂OMe ( 6 ), P(OMe)₃ ( 3 ), C₁₀H₈ (= 3 L) ( 4 ) and PMe₃ ( 5 )) are reported. Definite assignments of the ¹³C-NMR. resonances were made through the synthesis of [2, 3, 6, 7-²H₄]-naphthalene complexes. The coordinated ring ¹³C-resonance are found to undergo a smooth transition to higher field with increasing donor character of the coligands L. A correlation of the coordination shifts with the reactivity of the coordinated naphthalene is proposed. In complexes containing strong acceptor ligands the naphthalene is activated to attack by nucleophiles. Sequential treatment of complexes 1–4 , 6 and [C₁₀H₈FeC₅H₅]⁺[PF₆]^? ( 7 ) with stabilized carbanions and I₂ or Ce(IV)-salt yields α-substituted naphthalenes in the case of 1 , 2 , 6 and 7 but not in the case of 3 and 4 . Treatment of 3 with an excess of HBF₄ results not in the expected metal protonation but in a novel ligand transformation to yield 6 .     

Cationic hydrido-olefin complexes of ruthenium (II). The crystal structure of hydrido(1,3-butadiene)tris-(dimethylphenylphosphine)ruthenium(II) hexafluoro-phosphate

A route to the stable hydrido-diene salts [(diene)RuHL₃] PF₆, (diene = cycloocta-l,5-diene, hexa-l,3-diene and buta-1,3-diene, L = PMe₂ Ph; diene = cycloocta-l,5-diene, L = P(OMe)₃, P(OCH₂)₃ CMe P(OMe)Ph₂ and PMePh₂) has been found and the structure of [RuH(C₄H₆)(PMe₂Ph)₃] PF₆ has been determined by X-ray diffraction.     

Ruthenium piano-stool complexes bearing imidazole-based PN ligands

A variety of piano-stool complexes of cyclopentadienyl ruthenium(II) with imidazole-based PN ligands have been synthesized starting from the precursor complexes [CpRu(C₁₀H₈)]PF₆, [CpRu(NCMe)₃]PF₆ and [CpRu(PPh₃)₂Cl]. PN ligands used are imidazol-2-yl, -4-yl and -5-yl phosphines.Depending on the ligand and precursor different types of coordination modes were observed; in the case of polyimidazolyl PN ligands these were κ¹P-monodentate, κ²P,N-, κ²N,N- and κ³N,N,N- chelating and μ-κP:κ²N,N-brigding. The solid-state structures of [CpRu(1a)₂Cl ]·H₂O (5^.H₂O) and [{CpRu(μ-κ²-N,N-κ’¹-P-2b)}₂](C₆H₅PO₃H)₂(C₆H₅PO₃H₂)_2, a hydrolysis product of the as well determined [{CpRu(2b)}₂](PF₆)₂^.2CH₃CN (7b^.2CH₃CN) were determined (1a = imidazol-2-yldiphenyl phosphine, 2b = bis(1-methylimidazol-2-yl)phenyl phosphine, 3a = tris(imidazol-2-yl)phosphine). Furthermore, the complexes [CpRu(L)₂]PF₆ (L = imidazol-2-yl or imidazol-4-yl phosphine) have been screened for their catalytic activity in the hydration of 1-octyne.