An Unusual Product from the Reaction of C(PPh3)2 with [Mn2(CO)10]: Formation and Crystal Structure of [Mn(OPPh3)2{O2CC(PPh3)2}2][Mn(CO)5]2

The carbodiphosphorane C(PPh₃)₂ ( 1 ) reacts with [Mn₂(CO)₁₀] in THF to produce quantitatively the salt‐like complex (HC{PPh₃}₂)[Mn(CO)₅] ( 2 ) as THF solvate. If the reaction is carried out in 1,2‐dimethoxyethane (DME) small amounts of [Mn(OPPh₃)₂{O₂CC(PPh₃)₂}₂][Mn(CO)₅]₂ ( 3 ) as DME solvate along with solvent free 2 as the main product were isolated. Proton abstraction from the solvent led to the formation of 2 ; the ligands OPPh₃ and O₂CC(PPh₃)₂}₂ of 3 are the results of a side reaction from [Mn₂(CO)₁₀] and 1 in a Wittig type manner. From the reaction in benzene small amounts of 3 were also obtained, crystallizing as benzene solvate 3· 4C₆H₆. The crystal structures of 2· THF, 2 , 3· 1.75DME and 3· 4C₆H₆ are reported. The compounds are further characterized by IR and ³¹P NMR spectroscopy.     

The Ylide Adduct SOC2(PPh3)2 as Complex Ligand. Reaction with [Mn2(CO)10] and InCl3; Crystal Structures of [(CO)4Mn(SOC2{PPh3}2)2][Mn(CO)5] and (H2C{PPh3}2)[InCl4]2

The betain‐like SOC₂(PPh₃)₂ ( 1a ) reacts with [Mn₂(CO)₁₀] in THF to produce the salt‐like complex [(CO)₄Mn(SOC₂{PPh₃}₂)₂][Mn(CO)₅] ( 2 ). 1a is bonded via the sulfur atoms which are arranged in trans position in the octahedral environment of the manganese atom. With InCl₃ from CH₂Cl₂ solution the addition product [Cl₃In(SOC₂{PPh₃}₂)] ( 3 ) is obtained along with the salt (H₂C{PPh₃}₂)[InCl₄]₂ ( 4 ), which is the result of proton abstraction from the solvent. The crystal structures of 2· 0.5THF and 4· CH₂Cl₂ are reported. The compounds are further characterized by IR and ³¹P NMR spectroscopy.     

Reaction of S2CC(PPh3)2 with Silver Salts Containing Weakly Coordinating Anions; Preparation and Crystal Structures of [Ag6{S2CC(PPh3)2}4][BF4]6 · 9.75CH2CL2 and [Ag4{S2CC(PPh3)2}4][Al{OC(CF3)3}4]4 · 4.25C2H4Cl2

The betain‐like carbodiphosphorane CS₂ adduct S₂CC(PPh₃)₂ ( 1 ) reacts with Ag(I) salts which contain weakly coordinating anions such as [BF₄]^? or [Al{OC(CF₃)₃}₄]^? to produce the cluster compounds [Ag₆{S₂CC(PPh₃)₂}₄][BF₄]₆ ( 2 ) and [Ag₄{S₂CC(PPh₃)₂}₄][Al{OC(CF₃)₃}₄]₄ ( 3 ), respectively, as orange yellow crystals containing solvent molecules. In the solid state the Ag₄ unit in 3 forms a tetrahedron, and in the Ag₆ core of 2 two of the opposite edges of the tetrahedron are bridged by Ag⁺ ions. The clusters are held together by argentophilic interactions, and each sulfur atom of 1 is coordinated to four (as in 2 ) or three (as in 3 ) silver atoms. The compounds are characterized by IR and ³¹P NMR spectroscopic studies and by X‐ray diffraction analyses.     

Concerning the Reaction of the Betain‐Like Compound O2CC(PPh3)2 with Tungsten‐Carbonyl Derivatives; Preparation and Crystal Structures of [(CO)5W{η1‐O2C2(PPh3)2}] and [(CO)4W{η2‐O2C2(PPh3)2}]

The carbodiphosphorane CO₂ adduct O₂CC(PPh₃)₂ ( 1a ) reacts with [(CO)₅W(THF)] and [(CO)₃W(NCEt)₃] to produce the complexes [(CO)₅W{η¹‐O₂CC(PPh₃)₂}] ( 2 ) and [(CO)₄W{η²‐O₂CC(PPh₃)₂}] ( 3 ), respectively. Whereas in 2 the betain‐like ligand is coordinated at the tungsten atom in a monodentate manner, in 3 it acts as a chelating ligand with formation of a WO₂C four‐membered ring. As a by‐product during the reaction with the acetonitrile adduct also some crystals of the hydrolysis product [HC(PPh₃)₂]₂[W₆O₁₉] · 3C₂H₄Cl₂ (4 · 3C₂H₄Cl₂) were isolated. All compounds could be characterized by X‐ray analyses and the usual spectroscopic methods.     

The Coordination Chemistry of the Ylide Adduct O2CC(PPh3)2; Preparation,Crystal Structures,and Spectroscopic Properties of [Cl3In{O2CC(PPh3)2}], [Cl2Sn{O2CC(PPh3)2}], and [I2In{O2CC(PPh3)2}2]I

The betain like carbodiphosphorane CO₂ adduct O₂CC(PPh₃)₂ ( 1a ) can serve as a ligand versus hard Lewis acids from main group compounds. Thus, reaction of 1a with InCl₃, InI₃ and SnCl₂ in polar solvents leads to the addition compounds [Cl₃In{O₂CC(PPh₃)₂}] ( 2 ), [Cl₂SnO₂CC(PPh₃)₂}] ( 3 ) and the salt like compound [I₂In{O₂CC(PPh₃)₂}₂]I ( 4 ) in good yields. Whereas in the indium compounds 1a acts as a chelating ligand, in the tin compound the molecule coordinates with one oxygen atom only as a monodentate ligand. 4 has a pyramidal structure with a stereochemical active pair of electrons. All compounds could be characterized by X‐ray analyses and the usual spectroscopic methods.     

Reaktionen von Zinnchloriden mit Polysulfiden. Die Kristallstrukturen von (PPh4)2[SnCl2(S6)2], (PPh4)2[Sn4Cl4S5(S3)O] und (PPh4)2[SnCl6] · S8 · 2CH3CN

Reaction of Tin Chlorides with Polysulfides. Crystal Structures of (PPh₄)₂[SnCl₂(S₆)₂], (PPh₄)₂[Sn₄Cl₄S₅(S₃)O], and (PPh₄)₂[SnCl₆] · S₈ · 2CH₃CN . The reaction of PPh₄[SnCl₃] with Na₂S₄ in acetonitrile in the presence of small amounts of water yields (PPh₄)₂[Sn₄Cl₄S₅(S₃)O] and minor amounts of (PPh₄)₂[SnCl₂(S₆)₂], PPh₄Cl · 2S₈ and (PPh₄)₂[SnCl₆]. SnCl₄ is partially reduced by (PPh₄)₂S_x, PPh₄[SnCl₃] and (PPh₄)₂[SnCl₆] · S₈ · 2CH₃CN being produced. According to the X-ray crystal structure determination the [Sn₄Cl₄S₅(S₃)O]^2?-ion consists of an O atom that is coordinated by four Sn atoms which in turn are liked with one another by five single S atoms and one S₃ group. In the [SnCl₂(S₆)₂]^2?-ion the Sn atom is octahedrally coordinated by two Cl atoms in trans arrangement and by two chelating S₆ groups. Octahedral [SnCl₆]^2? ions and S₈ molecules in the crown conformation are present in (PPh₄)₄[SnCl₆] · S₈ · 2CH₃CN.     

Azidokomplexe von Mangan(II) und Cobalt(II) Die Kristallstrukturen von (PPh4)2[Mn(N3)4] und (PPh4)2[Co(N3)3Cl]

Azido Complexes of Manganese(II) and Cobalt(II). Crystal Structures of (PPh₄)₂[Mn(N₃)₄] and PPh₄₂[Co(N₃)₃Cl] (PPh₄)₂[Mn(N₃)₄] and (PPh₄)₂[Co(N₃)₃Cl] were obtained as light-brown and green blue, nonexplosive crystalline compounds, respectively. They are only slightly sensitive to moisture and were obtained from the tetrachloro complexes (PPh₄)₂MCl₄ by reactions with silver azide in dichloromethane. The compounds were characterized by thier i.r. spectra and by crystal structure analyses. Both crystallized in the monoclinic space group C2/c, Z = 4, but they are not isotypic. (PPh₄)₂[Mn(N₃)₄]: structure determination with 711 independent reflexions, R = 0.097; a = 2249.1, b = 1499.6, c = 1370.3 pm, β = 104.86°. (PPh₄)₂[Co(N₃)Cl]: 2753 reflexions, R = 0.075; a = 1119.7, b = 1899.2, c = 2115.4 pm, β = 90.47°. The structures consist of PPh₄⁺ ions and of anions that are situated on twofold crystallographic rotation axes. The anions show positional disorder, statistically assuming two different orientations with probabilities of 50% each; in the case of [Co(N₃)₃Cl]^2?, the Cl atom is superimposed statistically with an azido group, whereas the [Mn(N₃)₄]^2? ion is tilted by about 20° from the ideal position to two sides of the crystallographic axis. In both compounds the cation form layers and the anions are located between the layers.     

Formation of an Acyl‐Ethynyl‐Methylidyne Complex of Cobalt: Structure of Co3{μ3‐CC(O)C≡C[Ru(dppe)Cp*]}(CO)8(PPh3)

The reaction between Ru(C≡CH)(dppe)Cp* and Co₃(μ₃‐CBr)(CO)₉ in the presence of Pd(PPh₃)₄/CuI afforded dark red Co₃{μ₃‐CC(O)C≡C[Ru(dppe)Cp*]}(CO)₈(PPh₃), whose formation may involve attack of the Ru‐ethynyl fragment on an intermediate cluster‐bound CCO ligand; abstraction of PPh₃ from the palladium catalyst also occurs.     

Synthese und Kristallstrukturen von (PPh4)2[TeS3] · 2 CH3CN und (PPh4)2[Te(S5)2]

Synthesis and Crystal Structures of (PPh₄)₂[TeS₃] · 2 CH₃CN and (PPh₄)₂[Te(S₅)₂] (PPh₄)₂[TeS₃] · 2 CH₃CN was obtained by the reaction of PPh₄Cl, Na₂S₄ and Te in acetonitrile. With sulfur it reacts yielding (PPh₄)₂[Te(S₅)₂]. The crystal structures of both products were determined by X-ray diffraction. (PPh₄)₂[TeS₃] · 2 CH₃CN: triclinic, space group P1 , Z = 2, R = 0.041 for 4 629 reflexions; it contains trigonal-pyramidal [TeS₃]^2? ions with an average Te? S bond length of 233 pm. (PPh₃)₂[Te(S₅)₂]: monoclinic, P2₁/n, Z = 2, R = 0.037 for 2 341 reflexions. In the [Te(S₅)₂]^2? ion the tellurium atom has a nearly square coordination by four S atoms. Along with the Te atoms each of the two S₅ groups forms a ring with chair conformation.     

Redox properties of (RC2R')Co2(CO)6-nLn and reactivity of (RC2R')Co2(CO)6-nLn towards PPh3[LPPh3, P(OEt)3]

Cyclic voltammetric studies of clusters (C₅H₅-C₂C₆ H₄-R-p)Co₂(CO)6-n L_n[n=0,2; L=PPh₃, P(OEt)₃] and (RCH₂C)₂Co₂(CO₄) (PPh₃)₂ on Pt electrode are described. The primary reduction (0 / ?1) and oxidation (+ 1 / 0) steps are considered as a mono-electron process for all clusters. For the clusters (C₅H₅C₂C₆H₄-R-p)Co₂(CO)₆, a good linear relation between reduction potential E_p^red and Hammett constant σ_p of R in the clusters is found. For the clusters (RC₂R')Co₂(CO)₄L₂, their radical anions are extremely unstable at room temperature and fragment into a series of mononuclear species, one of which is (RC₂R')Co(CO)₂PPh₃. The reaction of radical anions of (RC₂R')Co₂(CO)_6–n (PPh₃)_n(n=0,2) with PPh₃ also produces mononuclear species (RC₂R')Co(CO)₂PPh₃ which has been detected by means of cyclic voltammetry and ESR. The influence of R on redox properties of clusters is discussed.     

Die Bildung von PPh4[WOCl4 · THF] und PPh4Cl · 4As4S3 aus W(CO)6 und PPh4[As2SCl5] sowie ihre Kristallstrukturen

Formation of PPh₄[WOCl₄ · THF] and PPh₄Cl · 4As₄S₃ from W(CO)₆ and PPh₄[As₂SCl₅] and their Crystal Structures When W(CO)₆ and PPh₄[As₂SCl₅] are irradiated with UV light in tetrahydrofurane, PPh₄[WOCl₄ · THF], PPh₄ Cl· 4As₄S₃ and PPh₄[Cl₂H] are obtained. X-ray crystal structure determinations were performed. PPh₄[WOCl₄ · THF], monoclinic, space group P2₁/c, Z = 4, a = 1207.5(2), b = 1003.7(2), c = 2642.0(5) pm, β = 114.71(1)°, R = 0.049% for 2824 reflexions; PPh₄⁺ and [WOCl₄. THF]^? ions are present, the WOCl₄ group having the shape of a tetragonal Pyramid with a short W ? O bond (169 pm) and the THF molecule being weakly associated (W? O 236 pm). PPh₄Cl · 4AsS₃, tetragonal, I4₁/a, Z = 4, a = 1742.3(3), c = 1664.5(4) pm, R = 0.066% for 1350 reflexions; it consists of separate PPh₄⁺ and Cl^? ions and As₄S₃ molecules.     

Reaktionen des [η2-{P–PtBu2}Pt(PPh3)2] und [η2-{P–PtBu2}Pt(dppe)] mit Metallcarbonylen. Bildung von [η2-{(CO)5M · PPtBu2}Pt(PPh3)2] (M = Cr,W) und [η2-{(CO)5Cr · PPtBu2}Pt(dppe)]

Coordination Chemistry of P-rich Phosphanes and Silylphosphanes. XVI [1] Reactions of [g²-{P–P^tBu₂}Pt(PPh₃)₂] and [g²-{P–P^tBu₂}Pt(dppe)] with Metal Carbonyls. Formation of [g²-{(CO)₅M · PP^tBu₂}Pt(PPh₃)₂] (M = Cr, W) and [g²-{(CO)₅Cr · PP^tBu₂}Pt(dppe)] [η²-{P–P^tBu₂}Pt(PPh₃)₂] 4 reacts with M(CO)₅ · THF (M = Cr, W) by adding the M(CO)₅ group to the phosphinophosphinidene ligand yielding [η²-{(CO)₅Cr · PP^tBu₂}Pt(PPh₃)₂] 1 , or [η²-{(CO)₅W · PP^tBu₂}Pt(PPh₃)₂] 2 , respectively. Similarly, [η²-{P–P^tBu₂}Pt(dppe)] 5 yields [η²-{(CO)₅Cr · PP^tBu₂}Pt(dppe)] 3 . Compounds 1 , 2 and 3 are characterized by their ¹H- and ³¹P-NMR spectra, for 2 and 3 also crystal structure determinations were performed. 2 crystallizes in the monoclinic space group P2₁/n (no. 14) with a = 1422.7(1) pm, b = 1509.3(1) pm, c = 2262.4(2) pm, β = 103.669(9)°. 3 crystallizes in the triclinic space group P1 (no. 2) with a = 1064.55(9) pm, b = 1149.9(1) pm, c = 1693.2(1) pm, α = 88.020(8)°, β = 72.524(7)°, γ = 85.850(8)°.     

Chelating and Tellurolate Ligand‐Transfer Studies of the Complex fac‐[Fe(CO)3(TePh)3]−: Crystal Structures of Heterodinuclear (CO)3Mn(μ‐TePh)3Fe(CO)3 and CpNi(TePh)(PPh3)

Complex fac‐[Fe(CO)₃(TePh)₃]^? was employed as a “metallo chelating” ligand to synthesize the neutral (CO)₃Mn(μ‐TePh)₃Fe(CO)₃ obtained in a one‐step synthesis by treating fac‐[Fe(CO)₃(TePh)₃]^? with fac‐[Mn‐(CO)₃(CH₃CN)₃]⁺. It seems reasonable to conclude that the d⁶ Fe(II) [(CO)₃Fe(TePh)₃]^? fragment is isolobal with the d⁶ Mn(I) [(CO)₃Mn(TePh)₃]^2? fragment in complex (CO)₃Mn(μ‐TePh)₃Fe(CO)₃. Addition of fac‐[Fe(CO)₃(TePh)₃]^? to the CpNi(I)(PPh₃) in THF resulted in formation of the neutral CpNi(TePh)(PPh₃) also obtained from reaction of CpNi(I)(PPh₃) and [Na][TePh] in MeOH. This investigation shows that fac‐[Fe(CO)₃(TePh)₃]^? serves as a tridentate metallo ligand and tellurolate ligand‐transfer reagent. The study also indicated that the fac‐[Fe(CO)₃(SePh)₃]^? may serve as a better tridentate metallo ligand and chalcogenolate ligand‐transfer reagent than fac‐[Fe(CO)₃(TePh)₃]^? in the syntheses of heterometallic chalcogenolate complexes.     

[(Te2)3{Mn(CO)3}2{Mn(CO)4}3]– – A Novel Tellurium‐­Manganese Carbonyl with Ufosane‐like Structure

By reacting Mn₂(CO)₁₀ and TeI₄ in the ionic liquid[BMIm][OTf] (1‐butyl‐3‐methylimidazolium trifluromethanesulfonate), brick‐red crystals of [BMIm][(Te₂)₃{Mn(CO)₃}₂{Mn(CO)₄}₃]are obtained. The title compound contains the carbonyl anion[(Te₂)₃{Mn(CO)₃}₂{Mn(CO)₄}₃]^–. Herein, three formal Te₂^2– units and two formal Mn(CO)₃⁺ fragments establish a distorted heterocubane‐like Te₆Mn₂ structure. Three edges of this heterocubane are furthermore capped by Mn(CO)₄⁺ fragments. The resulting Te₆Mn₅ building unit, moreover, looks very similar to the P₁₁^3– anion – the so‐called ufosane. The mean distances Te–Te and Te–Mn are observed with 277.6 and 264.7 pm, respectively. In addition to single‐crystal structure analysis, the title compound is characterized by infrared spectroscopy (FT‐IR), thermogravimetry (TG) and energy‐dispersive X‐ray (EDX) analysis.     

Synthesen und Strukturen neuer amido- und imidoverbrückter Cobaltcluster: [Li(THF)2]3[Co3(μ2-NHMes)3Cl6] (1), [Li(DME)3]2[Co18(μ4-NPh)3(μ3-NPh)12Cl3] (2), [Li(DME)3]2[Co6(μ4-NPh)(μ2-NPh)6(PPh2Et)2] (3) und [Li(THF)4][Co8(μ3-NPh)6(μ2-NPh)3(PPh3)2] (4)

Syntheses and Crystal Structures of new Amido- und Imidobridged Cobalt Clusters: [Li(THF)₂]₃[Co₃(μ₂-NHMes)₃Cl₆] (1), [Li(DME)₃]₂[Co₁₈(μ₄-NPh)₃(μ₃-NPh)₁₂Cl₃] (2), [Li(DME)₃]₂[Co₆(μ₄-NPh)(μ₂-NPh)₆(PPh₂Et)₂] (3), and [Li(THF)₄][Co₈(μ₃-NPh)₆(μ₂-NPh)₃(PPh₃)₂] (4) The reactions of cobalt(II)-chloride with the lithium-amides LiNHMes and Li₂NPh leads to an amido-bridged multinuclear complex [Li(THF)₂]₃[Co₃(μ₂-NHMes)₃Cl₆] ( 1 ) as well as to the imido-bridged cobalt cluster [Li(DME)₃]₂[Co₁₈(μ₄-NPh)₃(μ₃-NPh)₁₂Cl₃] ( 2 ). In the presence of tertiary phosphines two imido-bridged cobalt clusters [Li(DME)₃]₂[Co₆(μ₄-NPh)(μ₂-NPh)₆(PPh₂Et)₂] ( 3 ) and [Li(THF)₄][Co₈(μ₃-NPh)₆(μ₂-NPh)₃(PPh₃)₂] ( 4 ) result. The structures of 1 – 4 were characterized by X-ray single crystal structure analysis.     

Synthese und Kristallstrukturen von (PPh4)2[In(S4)(S6)Cl] und (PPh4)2[In(S4)Cl3]

Synthesis and Crystal Structures of (PPh₄)₂[In(S₄)(S₆)Cl] and (PPh₄)₂[In(S₄)Cl₃] InCl and PPh₄Cl yield (PPh₄)₂[In₂Cl₆] in acetonitrile. This reacts with Na₂S₄ in presence of PPh₄Cl, forming (PPh₄)₂[In(S₄)(S₆)Cl]. Its crystal structure was determined by X-ray diffraction (R = 0.075, 2 282 observed reflexions). It is isotypic with (PPh₄)₂[In(S₄)(S₆)Br] and contains anions with trigonal-bipyramidal coordination of In, Cl occupying an axial position, and the S₄ and S₆ groups being bonded in a chelate manner. The reaction of (PPh₄)₂[In₂Cl₆] and sulfur in acetonitrile yielded (PPh₄)₂[InCl₅] and (PPh₄)₂[In(S₄)Cl₃]. The crystal structure analysis of the latter (R = 0.072, 4 080 reflexions) revealed an anion with distorted trigonal-bipyramidal coordination of In, the S₄ group occupying one axial and one equatorial position; the S₄ group shows positional disorder.     

Kristallstrukturelle,Festkörper‐31P‐CP/MAS‐NMR,TOSS, 31P‐COSY‐NMR und mechanistische Beiträge zur Koordinationschemie des Octacarbonyldicobalts mit den Liganden Bis(diphenylphosphanyl)amin,Bis(diphenylphosphanyl)methan und 1,1,1‐Tris(diphenylphosphanyl)ethan

Chemistry of Polyfunctional Molecules. 133. X‐Ray Crystal Structural, Solid‐state ³¹P CP/MAS NMR, TOSS, ³¹P COSY NMR, and Mechanistic Contributions to the Co‐ordination Chemistry of Octacarbonyldicobalt with the Ligands Bis(diphenylphosphanyl)amine, Bis(diphenylphosphanyl)methane, and 1,1,1‐Tris(diphenylphosphanyl)ethane Co₂(CO)₈ reacts with bis(diphenylphosphanyl)amine, HN(PPh₂)₂ (Hdppa, 1 ), in two steps to afford the known compound [Co(CO)(Hdppa‐κ²P)₂][Co(CO)₄] · 2 THF ( 6 a · 2 THF). The intermediate [Co(CO)₂(Hdppa‐κ²P) · (Hdppa‐κP)][Co(CO)₄] · dioxane · n‐pentane ( 5 · dioxane · n‐pentane) was isolated for the first time and was characterized by X‐ray analysis. The cation 5 ⁺ exhibits a slightly distorted trigonal‐bipyramidal geometry. Detailed ³¹P‐NMR investigations (solid‐state CP/MAS NMR, TOSS, ³¹P‐COSY, ³¹P‐EXSY) showed that the additional tautomer [Co(CO)₂(Hdppa‐κ²P)(Ph₂P–N=P(H)Ph₂‐κP)]⁺ ( 5 ′⁺) is present in solution. The tautomer equilibrium is slow in the NMR time scale. In contrast to the solid state only tetragonal pyramidal species of 5 are found in solution. At –90 °C there is slow exchange between the three diastereomeric species 5 a ⁺– 5 c ⁺. Compound 5 forms [Co(CO) · (Hdppa‐κ²P)₂]BPh₄ · THF ( 6 b · THF) in THF with NaBPh₄ under CO‐Elimination. A X‐ray diffraction investigation shows that the cation 6 ⁺ consists of a slightly distorted trigonal‐bipyramidal co‐ordination polyeder. However, a distorted tetragonal‐pyramidal structure has been found for the cation 7 ⁺ of the related compound [Co(CO)(dppm)₂][Co(CO)₄] · 2 THF ( 7 · 2 THF; dppm = bis(diphenylphosphanyl)methane, Ph₂PCH₂PPh₂). A comparison with the known [8] trigonal‐bipyramidal stereoisomer, ascertained for 7 ⁺ of the solvent‐free 7 , is described. In solutions of 6 a · 2 THF and 7 · 2 THF ¹³C{¹H}‐ and ³¹P{¹H}‐NMR spectra indicate an exchange of all CO and organophosphane molecules between cobalt(I) cation and cobalt(–I) anion. A concerted mechanism for the exchange process is discussed. CO elimination leads to discontinuance of the cyclic mechanism by forming binuclear substitution products such as the isolated Co₂(CO)₂ · (μ‐CO)₂(μ‐dppm)₂ · 0.83 THF ( 8 · 0.83 THF), which was characterized by spectroscopy and X‐ray analysis. For the dissolved [Co(CO)₂CH₃C(CH₂PPh₂)₃][Co(CO)₄] · 0.83 n‐pentane ( 9 a · 0.83 n‐pentane) no CO and triphos exchange processes between the cation and the anion are observed. Metathesis of 9 a · 0.83 n‐pentane with NaBPh₄ yields [Co(CO)₂CH₃C(CH₂PPh₂)₃]BPh₄ ( 9 b ) which has been characterized by single‐crystal X‐ray analysis. The cation shows a small distorted tetragonal‐pyramidal structure.     

Permetalloplumbanes: Preparation of [Pb{Co(CO)3(L)}4] and [Pb{Fe(CO)2(NO)(L)}4].: Complexes containing four transition metal to lead bonds (L = tertiary arsine,phosphine or phosphite).

The sole and unexpected products from the reactions of a variety of lead (II) and lead (IV) compounds with [Co₂(CO)₆(L)₂] complexes (L = tertiary arsine, phosphine, or phosphite) in refluxing benzene solution are the blue, air-stable percobaltoplumbanes [Pb{Co(CO)₃(L)}₄]. These have also been obtained from the reaction of Na[Co(CO)₃(L)] (L  PBu₃ⁿ) with lead (II) acetate which with Na[Fe(CO)₂(NO)(L)] forms the isoelectronic [Pb{Fe(CO)₂(NO)(L)}₄] [L  P(OPh)₃]. The IR spectra of the complexes in the v(CO) and v(NO) regions are consistent with tetrahedral PbCo₄ or PbFe₄ fragments, trigonal bipyramidal coordination about the cobalt or iron atoms and linear PbCoAs, PbCoP, or PbFeP systems. Unlike [Pb{Co(CO)₄}₄], our complexes do not dissociate to [Co(CO)₃(L)]^? or [Fe(CO)₂(NO)(L)]^? ions when dissolved in donor solvents.     

Coordination Chemistry of P4S3 and P4Se3 towards the Iron Fragments [Fe(Cp)(CO)2]+ and [Fe(Cp)(PPh3)(CO)]+

The complexes Ag(L)_n[WCA] (L=P₄S₃, P₄Se₃, As₄S₃, and As₄S₄; [WCA]=[Al(OR^F)₄]⁻ and [F{Al(OR^F)₃}₂]⁻; R^F=C(CF₃)₃; WCA=weakly coordinating anion) were tested for their performance as ligand-transfer reagents to transfer the poorly soluble nortricyclane cages P₄S₃, P₄Se₃, and As₄S₃ as well as realgar As₄S₄ to different transition-metal fragments. As₄S₄ and As₄S₃ with the poorest solubility did not yield complexes. However, the more soluble silver-coordinated P₄S₃ and P₄Se₃ cages were transferred to the electron-poor Fp⁺ moiety ([CpFe(CO)₂]⁺). Thus, reaction of the silver salt in the presence of the ligand with Fp−Br yielded [Fp−P₄S₃][Al(OR^F)₄] ( 1 a ), [Fp−P₄S₃][F(Al(OR^F)₃)₂] ( 1 b ), and [Fp−P₄Se₃][Al(OR^F)₄] ( 2 ). Reactions with P₄S₃ also yielded [FpPPh₃−P₄S₃][Al(OR^F)₄] ( 3 ), a complex with the more electron-rich monophosphine-substituted Fp⁺ analogue [FpPPh₃]⁺ ([CpFe(PPh₃)(CO)]⁺). All complex salts were characterized by single-crystal XRD, NMR, Raman, and IR spectroscopy. Interestingly, they show characteristic blueshifts of the vibrational modes of the cage, as well as structural contractions of the cages upon coordination to the Fp/FpPPh₃ moieties, which oppose the typically observed cage expansions that lead to redshifts in the spectra. Structure, bonding, and thermodynamics were investigated by DFT calculations, which support the observed cage contractions. Its reason is assigned to σ and π donation from the slightly P−P and P−E antibonding P₄E₃-cage HOMO (e symmetry) to the metal acceptor fragment.     

Preparation of new (η5-C5H4CH3)Mn(NO)(PPh3) and (η7-C7H7)Mo(CO)-(PPh3) complexes

The complex (η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)I has been prepared by the reaction of NaI with [(η⁵-C₅H₄CH₃)Mn(NO)(CO)(PPh₃)]⁺ and also by the reaction of [(η⁵-C₅H₄CH₃)Mn(NO)(CO)₂]⁺ with NaI followed by PPh₃. This iodide compound reacts with NaCN to yield (η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)CN which is ethylated by [(C₂H₅)₃O]BF₄ to yield [(η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)(CNC₂H₅)]⁺. Both [(η⁵-C₅H₄CH₃)Mn(NO)(CO)₂]⁺ and [(η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)(CO)]⁺ react with NaCN to yield [(η⁵-C₅H₄CH₃)Mn(NO)(CN)₂]^?. This anion reacts with Ph₃SnCl to yield cis-(η⁵-C₅H₄CH₃)Mn(NO)(CN)₂SnPh₃ and with [(C₂-H₅)₃O]BF₄ to yield [(η⁵-C₅H₄CH₃)Mn(NO)(CNC₂H₅)₂]⁺. The reaction of (η⁵-C₅-H₄CH₃)Mn(NO)(PPh₃)I with AgBF₄ in acetonitrile yields [(η⁵-C₅H₄CH₃)Mn-(NO)(PPh₃)(NCCH₃)]⁺. The complex (η⁵-C₅H₄CH₃)Mn(NO)(CO)I, produced in the reaction of [(η⁵-C₅H₄CH₃)Mn(NO)(CO)₂]⁺ with NaI, is not stable and decomposes to the dimeric complex (η⁵-C₅H₄CH₃)₂Mn₂(NO)₃I for which a reasonable structure is proposed. Similar dimers can be prepared from the other halide salts. The reaction of (η⁷-C₇H₇)Mo(CO)(PPh₃)I with NaCN yields (η⁷-C₇-H₇)Mo(CO)(PPh₃)CN which is ethylated by [(C₂H₅)₃O]BF₄ to yield [(η⁷-C₇H₇)-Mo(CO)(PPh₃)(CNC₂H₅)]⁺. The interaction of this molybdenum halide complex with AgBF₄ in acetonitrile and pyridine yields [(η⁷-C₇H₇)Mo(CO)(PPh₃)-(NCCH₃)]⁺ and [(η⁷-C₇H₇)Mo(CO)(PPh₃)(NC₅H₅)]⁺, respectively. Both (η⁵-C₅-H₄CH₃)Mn(NO)(PPh₃)I and (η⁷-C₇H₇)Mo(CO)(PPh₃)I are oxidized by NOPF₆ to the respective 17-electron cations in acetonitrile at ?78°C but revert to the neutral halide complex at room temperature. This result is supported by electrochemical data.