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.     

Formation of the Salt‐like Complexes [Co{S2CC(PPh3)2}3][Co(CO)4]3 and [(CO)4Mn{S2CC(PPh3)2}][Mn(CO)5] from the Reaction of the Related Carbonyl Compounds with S2CC(PPh3)2

The betain‐like compound S₂CC(PPh₃)₂ ( 1 ), which is obtained from CS₂ and the double ylide C(PPh₃)₂, reacts with [Co₂(CO)₈] and [Mn₂(CO)₁₀] in THF to afford the salt‐like complexes [Co{S₂CC(PPh₃)₂}₃][Co(CO)₄]₃ ( 2 ) and [(CO)₄Mn{S₂CC(PPh₃)₂}][Mn(CO)₅] ( 3 ), respectively, in good yields. At both d⁶ cations 1 acts as a chelating ligand. Disproportionation reactions from formal Co⁰ into Co^III and Co^?I and from Mn⁰ into Mn^I and Mn^?I occurred with the removal of four or one carbonyl groups, respectively. The crystal structures of 2· 5.5THF and 3· 2THF are reported, which show a shortening of the C–C bond in the ligand upon complex formation. The compounds are further characterized by ³¹P NMR and IR 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.     

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.     

(PPh4)2[MoN(N3)3Cl]2; Synthese,IR-Spektrum und Kristallstruktur

(PPh₄)₂[MoN(N₃)₃Cl]₂; Synthesis, IR Spectrum, and Crystal Structure The title compound is formed in the reaction of molybdenum (II) benzoate with trimethylsilyl azide and PPh₄Cl in dichloro methane forming dark red single crystals. A PPh₃Me⊕ salt of the ion [MoN(N₃)₃Cl]₂^2? is obtained from (PPh₃Me)₂MoNCl₄] treated with silver azide in CH₂Cl₂ suspension. The solvent CH₂Cl₂ participates in both reactions as oxidizing agent. (PPh₄)₂[MoN(N₃)₃Cl₂ is characterized by a structural analysis based upon X-ray data: space group P1 , Z = 1, a = 1050.7 pm; b = 1185.4 pm; c = 1190.8 pm; α = 98.90°; β = 106.87°; γ = 103.97° (4505 independent, observed reflexions, R = 0.039). The compound consists of PPh₄⊕ cations and centrosymmetric anions [MoN(N₃)₃Cl₂^2? in which the molybdenum atoms are bridged by the N_α atoms of two azide groups; the resulting Mo? N bond lengths are 208 pm and 260 pm. In trans position to the long Mo? N bond the terminal nitrido ligand is situated, the Mo?N distance of 164 pm corresponds to a triple bond. Two terminal azido ligands and the chloro ligand are filling up the coordination sphere of the molybdenum atoms to a coordination number of six. The i.r. spectrum is reported and assigned.     

(PPh4)2[WO2Cl3]2 · 2 CH2Cl2: Synthese,Schwingungsspektrum und Kristallstruktur

(PPh₄)₂[WO₂Cl₃]₂ · 2 CH₂Cl₂. Synthesis, Vibrational Spectrum, and Crystal Structure Depending on the stoichiometry and the solvent, dichloromethane or 1.2-dichloroethane, WO₂Cl₂ reacts with tetraphenylphosphonium chloride affording (PPh₄)₂[WO₂Cl₄] or (PPh₄)₂[WO₂Cl₃]₂, respectively. Both compounds are easily soluble in dichloromethane, from which they can be crystallized under incorporation of two molecules CH₂Cl₂ per formula unit. The crystalline compounds have been characterized by their IR and Raman spectra. According to the X-ray crystal structure analysis, (PPh₄)₂[WO₂Cl₃]₂ · 2 CH₂Cl₂ crystallizes in the triclinic space group P1 with one formula unit per unit cell (986 independent observed reflexions, R = 0.061). Lattice constants: a = 1100.2, b = 1116.9, c = 1238.4 pm, = 69.40, = 80.46 and = 85.62°. The crystals consist of PPh₄^⊕ ions, centrosymmetric [WO₂Cl₃]₂^2? anions and CH₂Cl₂ molecules. In the anions, the tungsten atoms are linked via two oxo bridges with WO distances of 184 and 252 pm. The distorted octahedral coordination around each tungsten atom is completed by three terminal chloro and one terminal oxo ligand (WO bond length 166 pm), the latter being in trans position to the longer WO bridging bond. (PPh₄)₂[WO₂Cl₄] · 2 CH₂Cl₂ also forms triclinic crystals that are isotypic with (PPh₄)₂[WOCl₅] · 2 CH₂Cl₂ and in which the anions must have orientational disorder.     

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.     

Square-Planar Nickel(II) O,O′-Dialkyldithiophosphato Complexes with Triphenylphosphine of the Type [NiX(S2P{OR}2)(PPh3)] (X = Cl,Br, I and NCS)

A series of new [NiX(S₂P{O-c-Hex}₂)(PPh₃)](X = Cl^–, Br^–, I^– and NCS^–)(1)–(4) and [Ni(NCS)(S₂P{OR}₂)(PPh₃)][R =n-Pr (5), i-Pr (6)] complexes has been synthesized and characterized by elemental analyses, f.i.r., i.r., u.v.–vis., ¹H-, ¹³C{¹H}- and ³¹P{¹H}-n.m.r. spectra, magnetochemical and conductivity measurements. A single crystal X-ray analysis of [Ni(NCS)(S₂P{O-n-Pr}₂)(PPh₃)](5) reveals the molecular structure of the complex and confirms a square-planar geometry around the central atom of nickel with the NCS anion coordinated via the nitrogen atom.     

Synthese,Kristallstruktur und spektroskopische Charakterisierung von [Au12(PPh)2(P2Ph2)2(dppm)4Cl2]Cl2

Synthesis, Crystal Structure and Spectroscopic Characterization of [Au₁₂(PPh)₂(P₂Ph₂)₂(dppm)₄Cl₂]Cl₂ The reaction of [(AuCl)₂dppm] (dppm = Ph₂PCH₂PPh₂) with P(Ph)(SiMe₃)₂ in CHCl₃ results in the formation of [Au₁₂(PPh)₂(P₂Ph₂)₂(dppm)₄Cl₂]Cl₂ ( 1 ), the crystal structure of which was determined by single crystal X‐ray analysis (space group P2₁/c, a = 1425.3(3) pm, b = 2803.7(6) pm, c = 2255.0(5) pm, β = 95.00(3)°, V = 8977(3)·10⁶ pm³, Z = 2). The dication in 1 consists of two Au₆P₃ units built by highly distorted Au₃P and Au₂P₂ heterotetrahedra, connected via four bidentate phosphine ligands. Additionally, the compound was characterized by IR‐, UV‐ and NMR spectroscopy. The ³¹P{¹H} NMR spectrum is discussed in detail.     

Reaction of (PPh3)2C→CO2 with Halogenated Hydrocarbons; Formation and Crystal Structure of a Cationic Ester with 1, 2‐Dichloroethane

The carbodiphosphorane CO₂ adduct ( 2 ) reacts slowly with 1, 2‐dichloroethane to give (HC{PPh₃}₂)Cl ( 5 ) as result of HCl abstraction along with the ester‐like salt (ClCH₂CH₂O(O)CC{PPh₃}₂)Cl ( 4 ) from nucleophilic substitution of one Cl^– by 2 . Both compounds could be separated by fractional crystallization. Attempts to dissolve 2 in 1, 2‐difluorobenzene leads to small amounts of the hydrolysis product (HC{PPh₃}₂)(HCO₃) · H₂O ( 6· H₂O) caused by some humidity in the solvent. All compounds could be crystallized and the structures studied by X‐ray analyses and ³¹P NMR spectroscopy.     

Crystal Structures of [Bu2Sn(O2PPh2)2], [Ph2Sn(O2PPh2)2], and [PhClSn(O2PPh2)OMe]2. Raman Spectra of [Ph2Sn(O2PPh2)2] and [PhClSn(O2PPh2)OMe]2

[(n‐Bu)₂Sn(O₂PPh₂)₂] ( 1 ), and [Ph₂Sn(O₂PPh₂)₂] ( 2 ) have been synthesized by the reactions of R₂SnCl₂ (R=n‐Bu, Ph) with HO₂PPh₂ in Methanol. From the reaction of Ph₂SnCl₂ with diphenylphosphinic acid a third product [PhClSn(O₂PPh₂)OMe]₂ ( 3 ) could be isolated. X‐ray diffraction studies show 1 to crystallize in the monoclinic space group P2₁/c with a = 1303.7(1) pm, b = 2286.9(2) pm, c = 1063.1(1) pm, β = 94.383(6)°, and Z = 4. 2 crystallizes triclinic in the space group , the cell parameters being a = 1293.2(2) pm, b = 1478.5(4) pm, c = 1507.2(3) pm, α = 98.86(3)°, β = 109.63(2)°, γ = 114.88(2)°, and Z = 2. Both compounds form arrays of eight‐membered rings (SnOPO)₂ linked at the tin atoms to form chains of infinite length. The dimer 3 consists of a like ring, in which the tin atoms are bridged by methoxo groups. It crystallizes triclinic in space group with a = 946.4(1) pm, b = 963.7(1) pm, c = 1174.2(1) pm, α = 82.495(6)°, β = 66.451(6)°, γ = 74.922(6)°, and Z = 1 for the dimer. The Raman spectra of 2 and 3 are given and discussed.     

Darstellung,Strukturen und EPR-Spektren der Rhenium(II)-Nitrosylkomplexe [Re(NO)Cl2(PPh3)(OPPh3)(OReO3)], [Re(NO)Cl2(OPPh3)2(OReO3)] und [Re(NO)Cl2(OPPh3)3](ReO4)

Synthesis, Structures, and EPR-Spectra of the Rhenium(II) Nitrosyl Complexes [Re(NO)Cl₂(PPh₃)(OPPh₃)(OReO₃)], [Re(NO)Cl₂(OPPh₃)₂(OReO₃)], and [Re(NO)Cl₂(OPPh₃)₃](ReO₄) The paramagnetic rhenium(II) nitrosyl complexes [Re(NO)Cl₂(PPh₃)(OPPh₃)(OReO₃)], [Re(NO)Cl₂(OPPh₃)₂ · (OReO₃)], and [Re(NO)Cl₂(OPPh₃)₃](ReO₄) are formed during the reaction of [ReOCl₃(PPh₃)₂] with NO gas in CH₂Cl₂/EtOH. These and two other Re^II complexes with 5 d⁵ ”︁low-spin”︁”︁-configuration can be observed during the reaction EPR spectroscopically. Crystal structure analysis shows linear coordinated NO ligands (Re–N–O-angles between 171.9 and 177.3°). Three OPPh₃ ligands are meridionally coordinated in the final product of the reaction, [Re(NO)Cl₂(OPPh₃)₃][ReO₄] (monoclinic, P2₁/c, a = 13.47(1), b = 17.56(1), c = 24.69(2) Å, β = 95.12(4)°, Z = 4). [Re(NO)Cl₂(PPh₃)(OPPh₃)(OReO₃)] (triclinic P 1, a = 10.561(6), b = 11.770(4), c = 18.483(8) Å, α = 77.29(3), β = 73.53(3), γ = 64.70(4)°, Z = 2) and [Re(NO)Cl₂ (OPPh₃)₂(OReO₃)] (monoclinic P2₁/c, a = 10.652(1), b = 31.638(4), c = 11.886(1) Å, β = 115.59(1)°), Z = 4) can be isolated at shorter reaction times besides the complexes [Re(NO)Cl₃(Ph₃P)₂], [Re(NO)Cl₃(Ph₃P) · (Ph₃PO)], and [ReCl₄(Ph₃P)₂].     

Reactions of [ReOX3(PPh3)2] Complexes (X = Cl,Br) with Phenylacetylene and the Structures of the Products

Oxorhenium(V) complexes [ReOX₃(PPh₃)₂] (X = Cl, Br) react with phenylacetylene under formation of complexes with ylide‐type ligands. Compounds of the compositions [ReOCl₃(PPh₃){C(Ph)C(H)(PPh₃)}] ( 1 ), [ReOBr₃(OPPh₃){C(Ph)C(H)(PPh₃)}] ( 2 ), and [ReOBr₃(OPPh₃){C(H)C(Ph)(PPh₃)}] ( 3 ) were isolated and characterized by X‐ray diffraction. They contain a ligand, which was formed by a nucleophilic attack of released PPh₃ at coordinated phenylacetylene. The structures of the products show that there is no preferable position for this attack. Cleavage of the Re–C bond in 3 and dimerization of the organic ligand resulted in the formation of the [{(PPh₃)(H)CC(Ph)}₂]²⁺ cation, which crystallized as its [(ReOBr₄)(OReO₃)]^2– salt.     

Synthesis and Characterization of Pyrrolthiosemicarbazone Complexes of Palladium(II). Crystal Structures of [{Pd[C4H4NC(H)=NNC(S)NHMe](Cl)}2{μ‐Ph2P(CH2)3PPh2}] and [Pd{C4H4NC(H)=NNC(S)NHMe}{Ph2P(CH2)2PPh2‐P,P}](Cl)

Reaction of the thiosemicarbazone ligands C₄H₄NC(H)=NN(H)C(S)NHR (R = Me, a ; Et, b ) with Li₂[PdCl₄] gave the dinuclear complexes [Pd{C₄H₄NC(H)=NNC(S)NHR}(μ‐Cl)]₂ (R = Me, 1a ; Et, 1b ) with a central Pd₂Cl₂ core and with deprotonation of the thiosemicarbazones at the hydrazinic nitrogen atom. Treatment of 1a and 1b with triphenylphosphine gave the mononuclear compounds [Pd{C₄H₄C(H)=NNC(S)NHR}(Cl)(PPh₃)] (R = Me, 2a ; Et, 2b ), whereas reaction of 1a and 1b with tertiary diphosphines gave mono‐ and dinuclear compounds, as appropriate, with the corresponding diphosphine acting as a monodentate ( 6b ), chelating ( 3a ) and bridging ligand ( 4a, 5a , 4b, 5b ). Treatment of 1a and 1b with (Ph₂PCH₂CH₂PPh₂)W(CO)₅ gave the new heterobimetallic complexes 7a and 7b . The crystal structures of complexes 3a and 4a are described.     

Addukte des Oxo-tetrachloro-niobat(V)-Ions Bildung,Schwingungsspektren und Kristallstrukturen von PPh4[NbOCl4(OH2)] und (PPh4)2[NbOCl4(O2PCl2)] · 2 CH2Cl2

Adducts of Oxotetrachloro-niobate (V). Formation, Vibrational Spectra, and Crystal Structures of PPh₄[NbOCl₄(OH₂)] and (PPh₄)₂[NbOCl₄(O₂PCl₂)] · 2 CH₂Cl₂ Crystalline (PPh₄)₂[NbOCl₄(O₂PCl₂)] · 2 CH₂Cl₂ was obtained by hydrolysis of PPh₄[NbSCl₄] in the presence of POCl₃ in CH₂Cl₂. Experiments to obtain the same compound from PPh₄Cl, POCl₃, NbCl₅, and H₂O yielded PPh₄[NbOCl₄(OH₂)]. I.R. spectra of both compounds are discussed. The crystal structure determinations with X-ray diffraction data in both cases show quadratic-pyramidal NbOCl₄^? ions to which a molecule of either H₂O or a PO₂Cl₂^? ion is attached in trans-position to the O atom. PPh₄[NbOCl₄(OH₂)]: tetragonal, space group P4/n, a = 1 308, c = 734 pm, Z = 2, packing as in the AsPh₄[RuNCl₄] type; refinement down to R = 0.046 for 681 reflexions. (PPh₄)₂[NbOCl₄(O₂PCl₂)] · 2 CH₂Cl₂: triclinic, space group P1 , a = 1172, b = 1187, c = 2105 pm, α = 88.40, β = 83.20, γ = 71.28°, Z = 2, packing similar as in (AsPh₄)₂[NbOCl₅] · 2 CH₂Cl₂; refinement to R = 0.059 for 2 502 reflexions.     

Darstellung und Kristallstrukturen von Ag[N(CN)2](PPh3)2, Cu[N(CN)2](PPh3)2 und Ag[N(CN)2](PPh3)3

Preparation and Crystal Structures of Ag[N(CN)₂](PPh₃)₂, Cu[N(CN)₂](PPh₃)₂, and Ag[N(CN)₂](PPh₃)₃ The coordination compounds Ag[N(CN)₂](PPh₃)₂ ( 1 ), Cu[N(CN)₂](PPh₃)₂ ( 2 ), and Ag[N(CN)₂](PPh₃)₃ ( 3 ) are obtained by the reaction of AgN(CN)₂ or CuN(CN)₂ with triphenylphosphane in CH₂Cl₂. X‐ray structure determinations were performed on single crystals of 1 , 2 , and 3 · C₆H₅Cl. The three compounds crystallize monoclinic in the space group P2₁/n with the following unit cell parameters. 1 : a = 1216.07(9), b = 1299.5(2), c = 2148.4(3) pm, β = 99.689(13)°, Z = 4; 2 : a = 1369.22(10), b = 1257.29(5), c = 1888.04(15) pm, β = 94.395(7)°, Z = 4; 3 · C₆H₅Cl: a = 1276.6(4), b = 1971.7(3), c = 2141.3(5) pm, β = 98.50(3)°, Z = 4. In all structures the metal atoms have a distorted tetrahedral coordination. The crystal structure of 3 · C₆H₅Cl shows monomeric molecular units with terminal coordinated dicyanamide. The crystal structure of 1 is built up by dinuclear units, which are bridged by dicyanamide ligands. However, the crystal structure of 2 corresponds to a onedimensional coordination polymer, bridged by dicyanamide anions.     

The Reaction of the Betain‐like Compound O2C2(PPh3)2 with [(cod)PtI2] – Crystal Structure of the Salt (HC{PPh3}2)[(η3‐C8H11)PtI2]

The reaction of the betain‐like compound O₂C₂(PPh₃)₂ ( 1 ) with [(cod)PtX₂] in THF solution gives the salt‐like compounds (HC{PPh₃}₂)[(η³‐C₈H₁₁)PtX₂] ( 3 , X = I; 4 , X = Cl) in about quantitative yields. The new η³‐bonded C₈H₁₁ ligand is the result of a proton transfer from the coordinated cod ligand to 1 with subsequent release of CO₂. The X‐ray analysis of 3 shows the presence of two isomers in a 60:40 ratio, which differ in the bonding of the C₈H₁₁ ligand. 3 crystallizes in the triclinic space group with the unit cell dimensions a = 1091.7(1), b = 1141.5(1), c = 1649.4(2) pm; α = 80.34(1)°, β = 83.62(1)°, γ = 89.03(1)°, V = 2013.7(4)·10⁶ pm³, Z = 2.     

Reactivity of a rhodium(I) complex towards oxygen enhanced by a cyano ligand. Structure of [Rh(CN)(O2)(PPh3)2(XNC)] (XNC=xylyl isocyanide)

The complex [Rh(CN)(O₂)(PPh₃)₂(XNC)](CH₂Cl₂) has been obtained under ambient conditions from solutions containing trans-[Rh(CN)(PPh₃)₂(XNC)] upon exposure to air. The compound is unusual in that analogues containing the more strongly electron-donating ligands Cl⁻, N₃⁻ and NCO⁻ (among others) in place of CN⁻ are not formed.     

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.