Über den Phosphandiyl‐Transfer von invers‐polarisierten Phosphaalkenen R1P=C(NMe2)2 (R1 = tBu,Cy, Ph,H) auf Phospheniumkomplexe [(η5‐C5H5)(CO)2M=P(R2)R3] (R2 = R3 = Ph; R2 = tBu,R3 = H; R2 = Ph,R3 = N(SiMe3)2)

Phosphanediyl Transfer from Inversely Polarized Phosphaalkenes R¹P=C(NMe₂)₂ (R¹ = tBu, Cy, Ph, H) onto Phosphenium Complexes [(η⁵‐C₅H₅)(CO)₂M=P(R²)R³] (R² = R³ = Ph; R² = tBu, R³ = H; R² = Ph, R³ = N(SiMe₃)₂) Reaction of the freshly prepared phosphenium tungsten complex [(η⁵‐C₅H₅)(CO)₂W=PPh₂] ( 3 ) with the inversely polarized phosphaalkenes RP=C(NMe₂)₂ ( 1 ) ( a : R = tBu; b : Cy; c : Ph) led to the η²‐diphosphanyl complexes ( 9a‐c ) which were isolated by column chromatography as yellow crystals in 24‐30 % yield. Similarly, phosphenium complexes [(η⁵‐C₅H₅)(CO)₂M=P(H)tBu] (M = W ( 6 ); Mo ( 8 )) were converted into (M = W ( 11 ); Mo ( 12 )) by the formal abstraction of the phosphanediyl [PtBu] from 1a . Treatment of [(η⁵‐C₅H₅)(CO)₂W=P(Ph)N(SiMe₃)₂] ( 4 ) with HP=C(NMe₂)₂ ( 1d ) gave rise to the formation of yellow crystalline ( 10 ). The products were characterized by elemental analyses and spectra (IR, ¹H, ¹³C‐, ³¹P‐NMR, MS). The molecular structure of compound 10 was elucidated by an X‐ray diffraction analysis.     

Aktivierung von Schwefelkohlenstoff an Trirutheniumclustern: Synthese und Kristallstruktur von [Ru3(CO)5(μ‐H)2(μ‐PCy2)(μ‐Ph2PCH2PPh2){μ‐η2‐PCy2C(S)}(μ3‐S)] und [Ru3(CO)5(CS)(μ‐H)(μ‐PtBu2)(μ‐PCy2)2(μ3‐S)]

Activation of Carbon Disulfide on Triruthenium Clusters: Synthesis and X‐Ray Crystal Structure Analysis of [Ru₃(CO)₅(μ‐H)₂(μ‐PCy₂)(μ‐Ph₂PCH₂PPh₂){μ‐η²‐PCy₂C(S)}(μ₃‐S)] and [Ru₃(CO)₅(CS)(μ‐H)(μ‐P^tBu₂)(μ‐PCy₂)₂(μ₃‐S)] [Ru₃(CO)₆(μ‐H)₂(μ‐PCy₂)₂(μ‐dppm)] ( 1 ) (dppm = Ph₂PCH₂PPh₂) reacts under mild conditions with CS₂ and yields by oxidative decarbonylation and insertion of CS into one phosphido bridge the opened 50 VE‐cluster [Ru₃(CO)₅(μ‐H)₂(μ‐PCy₂)(μ‐dppm){μ‐η²‐PCy₂C(S)}(μ₃‐S)] ( 2 ) with only two M–M bonds. The compound 2 crystallizes in the triclinic space group P 1 with a = 19.093(3), b = 12.2883(12), c = 20.098(3) Å; α = 84.65(3), β = 77.21(3), γ = 81.87(3)° and V = 2790.7(11) ų. The reaction of [Ru₃(CO)₇(μ‐H)(μ‐P^tBu₂)(μ‐PCy₂)₂] ( 3 ) with CS₂ in refluxing toluene affords the 50 VE‐cluster [Ru₃(CO)₅(CS)(μ‐H)(μ‐P^tBu₂)(μ‐PCy₂)₂(μ₃‐S)] ( 4 ). The compound cristallizes in the monoclinic space group P 2₁/a with a = 19.093(3), b = 12.2883(12), c = 20.098(3) Å; β = 104.223(16)° and V = 4570.9(10) ų. Although in the solid state structure one elongated Ru–Ru bond has been found the complex 4 can be considered by means of the ³¹P‐NMR data as an electron‐rich metal cluster.     

Halogen‐bridged Cationic Complexes of the Type [{CpM(CO)3}2X]SbF6 (M = Mo,W; X = Cl,I), [{CpW(CO)2Cl2}2Cl]SbCl6, and the Trichloride CpW(CO)2Cl3

The reaction of CpMo(CO)₃X (X = Cl, I) with SbF₅ in toluene leads to the cationic, halogen bridged compounds [{CpMo(CO)₃}₂X]SbF₆ ( 1 , 2 ). CpW(CO)₃Cl reacts with SbF₅ to yield [{CpW(CO)₃}₂Cl]SbF₆ ( 3 ), whereas with SbCl₅, the oxidative substitution product [{CpW(CO)₂Cl₂}₂Cl]SbCl₆ ( 4 ) is formed, which decomposes in solution to yield the trichloride CpW(CO)₂Cl₃ ( 5 ). The strong Lewis acid SbF₅ separates the halide from CpM(CO)₃X (M = Mo, W), and the resulting cationic fragment “CpM(CO)₃⁺” reacts with a further CpM(CO)₃X forming a halonium bridge ( 1 – 3 ). The exclusive formation of SbF₆^– can be explained by the oxidizing power of SbF₅. The IR, MS and NMR spectra of the compounds 1 – 5 as well as the X‐ray structure analysis of 5 are reported and discussed.     

Metallkomplexe von Phenylenbistriazeniden: Synthese und Kristallstrukturen von [Cp(CO)2M]2(1,2-PhN3C6H4N3Ph) (M = Mo,W)

Metal Complexes of Phenylenebistriazenides: Synthesis and Crystal Structures of [Cp(CO)₂M]₂(1,2-PhN₃C₆H₄N₃Ph) (M = Mo, W) [Cp(CO)₂M]₂(1,2-PhN₃C₆H₄N₃Ph) [(M = Mo( 1 ), M = W( 2 )] is formed in the reaction of Cp(CO)₃MCl with PhN₃(H)C₆H₄N₃(H)Ph and C₂H₅ONa in a THF/ethanol mixture. 1 crystallizes from toluene as dark red crystals (triclinic, P1 , a = 1 499.3(9) pm, b = 1 734.0(7) pm, c = 1 852.8(8) pm, α = 66.84(3)°, β = 78.25(4)°, γ = 77.19(4)°). The unit cell contains four complexes with two independent complexes in the asymmetric unit, and eight solvent molecules. 2 crystallizes from THF as yellow crystals free from solvent molecules (triclinic, P1 , a = 979.0(5) pm, b = 1 152.8(5) pm, c = 1 475.8(5) pm, α = 98.26(4)°, β = 104.93(4)°, γ = 101.03(4)°, Z = 2). 1 and 2 are discrete molecular complexes with a 1,2-bis(phenyltriazenido)phenylligand, (PhN₃C₆H₄N₃Ph)^2?, chelating the metal atoms of two Cp(CO)₂M units with the N atoms N1 and N3 of both N₃ groups. Due to the sterical pretension of the Cp(CO)₂M units the phenylenebistriazenido ligand deviates strongly from planarity that is found in the metal complexes characterized so far.     

N,N, N′, N′‐Tetrakis(diphenylphosphanyl)‐1, 3‐diaminobenzene as a Bis‐chelate Ligand in [1, 3‐{cis‐Mo(CO)4(PPh2)2N}2C6H4]

1, 3‐Diaminobenzene reacts readily with PPh₂Cl to give N, N, N′, N′‐tetrakis(diphenylphosphanyl)‐1, 3‐diaminobenzene ( 1 ) in excellent yield. The dinuclear complex [1, 3‐{cis‐Mo(CO)₄(PPh₂)₂N}₂C₆H₄] ( 2 ) is obtained in high yield from 1 and cis‐[Mo(CO)₄(NCEt)₂]. Compounds 1 and 2 were characterized by NMR spectroscopy (¹H, ¹³C, ³¹P) and by crystal structure determination. The latter shows the formation of a bis‐chelate complex with Mo‐P‐N‐P four‐membered rings.     

Neutrale Bis‐Aziridin‐Komplexe des Typs [M(CO)3XAz2] (M = Mn,Re; X = Cl,Br; Az = N(H)C2H2Me2)

The pentacarbonylhalogene complexes [XM(CO)₅] (M = Mn, Re; X = Cl, Br) ( 1a – 2b ) react with 2,2‐dimethylaziridine by thermally induced substitution reaction to give the neutral bis‐aziridine complexes [M(X)(CO)₃Az₂] (Az = N(H)C₂H₂Me₂) ( 3a – 4b ). As a result of the X‐ray structure analyses, the metal atoms are octahedrally configurated in the facial arrangement; the intact three‐membered rings coordinate through their distorted tetrahedrally configurated N atoms. All compounds 3a – 4b are stable with respect to the directed thermal alkene elimination to give the corresponding nitrene complexes (CO)₄(X)M=NH; their IR, ¹H and ¹³C{¹H} NMR, and MS spectra are reported and discussed.     

Neue Phosphaniminato‐Komplexe von Molybdän und Wolfram. Die Kristallstrukturen von [(μ‐S2N2){MoCl4(NPPh3)}2], [Mo(NPPh3)4][BF4]2, [W(S)2(NPPh3)2] und [Ph3PNH2]+[SCN]–

New Phosphoraneiminato Complexes of Molybdenum and Tungsten. Crystal Structures of [(μ‐S₂N₂){MoCl₄(NPPh₃)}₂], [Mo(NPPh₃)₄][BF₄]₂, [W(S)₂(NPPh₃)₂], and [Ph₃PNH₂]⁺[SCN]^– The binuclear molybdenum(V)phosphoraneiminato complex [(μ‐S₂N₂){Mo^VCl₄(NPPh₃)}₂] ( 1 ) has been prepared by the reaction of the chlorothionitreno complex [Mo^VICl₄(NSCl)]₂ with Me₃SiNPPh₃ in dichloromethane forming green crystals. The temperature dependent magnetic susceptibility in the range of 2–30 K shows ideal behaviour according to the Curie law with a magnetic moment of 1.60 B.M. According to the crystal structure determination 1 forms centrosymmetric molecules in which the molybdenum atoms are connected by the nitrogen atoms of the S₂N₂ molecule. In trans‐position to it the nitrogen atoms of the phosphoraneiminato groups (NPPh₃^–) are coordinated with Mo–N bond lengths of 171(1) pm. The tetrakis(phosphoraneiminato) complex [Mo(NPPh₃)₄]‐ [BF₄]₂ ( 2 ) has been obtained as colourless crystal needles by the reaction of MoN(NPPh₃)₃ with boron trifluoride etherate in toluene solution. In the dication the molybdenum atom is tetrahedrally coordinated by the nitrogen atoms of the (NPPh₃^–) groups with Mo–N bond lengths of 179,8–181,0(3) pm. The dithio‐bis(phosphoraneiminato) tungsten complex [W(S)₂(NPPh₃)₂] ( 3 ) is formed as yellow crystals as well as [Ph₃PNH₂]⁺[SCN]^– ( 4 ) from the reaction of WN(NPPh₃)₃ with carbon disulfide in tetrahydrofurane in the presence of traces of water. 3 has a monomeric molecular structure with tetrahedrally coordinated tungsten atom with bond lengths W–S of 214.5(5) pm and W–N of 179(1) pm. In the structure of 4 the thiocyanate ions are associated by hydrogen bonds of the NH₂ group of the [Ph₃PNH₂]⁺ ion to give a zigzag chain. 1 : Space group Pbca, Z = 4, lattice constants at –80 °C: a = 1647.9(3), b = 1460.8(2), c = 1810.4(4) pm; R₁ = 0.0981. 2 : Space group P1, Z = 2, lattice constants at –80 °C: a = 1162.5(1), b = 1238.0(1), c = 2346.2(2) pm; α = 103.14(1)°, β = 90.13(1)°, γ = 97.66(1)°; R₁ = 0.0423. 3 : Space group Fdd2, Z = 8, lattice constants at –80 °C: a = 3310.1(4), b = 2059.7(2), c = 966,7(1) pm; R₁ = 0.0696. 4 : Space group P2₁2₁2₁, Z = 4, lattice constants at –80 °C: a = 1118.4(1), b = 1206.7(1), c = 1279.9(1) pm; R₁ = 0.0311.     

[Ph4P][(C5H6N3O3)M(CO)5] (M = Cr,Mo, W; C5H7N3O3 = 1,3‐Dimethyl‐cyanuric Acid). Organometallic Complexes of the 1,3‐Dimethylcyanurate Ligand

1,3‐Dimethylcyanuric acid (DMCH) forms on deprotonation and reaction with TlF its thallous salt Tl[DCM] ( 2 ) which is converted to the phosphonium salt [PPh₄][DCM] ( 3 ). On the reaction with M(CO)₆, the pentacarbonylmetalate salts [Ph₄P][(DMC)M(CO)₅], M = Cr ( 4a ), Mo ( 4b ) and W ( 4c ) are obtained. IR and NMR data of 4 reveal the DMC anion ( 1 ) to have coordination properties similar to those of pyridine. The crystal structures of 4a and 4c are reported.     

Übergangsmetall-Silyl-Komplexe, 44. Darstellung der zweikernigen Silyl-Komplexe (CO)3(R3Si)Fe(μ-PR′R′′)Pt(PPh3)2 durch oxidative Addition von (CO)3(R′R′′HP)Fe(H)SiR3 an (C2H4)Pt(PPh3)2

Transition Metal Silyl Complexes, 44. — Preparation of the Binuclear Silyl Complexes (CO)₃(R₃Si)Fe(μ-PR′R′′)Pt(PPh₃)₂ by Oxidative Addition of (CO)₃(R′R′′HP)Fe(H)SiR₃ to (C₂H₄)Pt(PPh₃)₂ The complexes (CO)₃(R′R′′HP)Fe(H)SiR₃ ( 1 ) [PHR′R′′ = PHPh₂, PH₂Ph, PH₂Cy; SiR₃ = SiPh₃, SiPh₂Me, SiPhMe₂, Si(OMe)₃] react with Pt(C₂H₄)(PPh₃)₂ to give the dinuclear, silyl-substituted complexes (CO)₃(R₃Si)Fe(μ-PR′R′′)Pt(PPh₃)₂ ( 2 ) in high yields. Upon reaction of 2 (R = R′ R′′ = Ph) with CO, the PPh₃ ligand at Pt being trans to the PPh₂ bridge is exchanged, and (CO)₃(Ph₃Si)Fe(μ-PPh₂)Pt(PPh₃)CO ( 3 ) is formed. Complex 3 is characterized by an X-ray structure analysis. The rather short Fe — Si distance [233.9(2) pm] and the infrared spectrum of 3 indicate that the Fe — Pt bond is quite polar.     

Perfluormethyl‐Element‐Liganden. XLIII [1] Neue Synthesewege zu Zweikernkomplexen des Typs MM′(CO)8ER2X (M/M′ = Mn/Mn,Mn/Re,Re/Re; E = P,As; R = CF3, Me; X = Hal)

Perfluoromethyl Element Ligands. XLIII [1] Novel Synthetic Routes to Binuclear Complexes of the Type MM′(CO)₈ER₂X (M/M′ = Mn/Mn, Mn/Re, Re/Re; E = P, As; R = CF₃, Me; X = Hal, ) Mn(CO)₅I reacts with compounds of the type (CF₃)₂EAsMe₂ (E = P, As) as with the symmetric E₂(CF₃)₄ ligands in the first step with cleavage of the E‐As bond to yield the pro ducts (CO)₅MnE(CF₃)₂ and Me₂AsI. Reaction of the mononuclear complexes with excess of Mn(CO)₅I leads in good yields to the known dinuclear compounds (CO)₄Mn[E(CF₃)₂, I]Mn(CO)₄ and CO. Me₂AsI, the second product of the EAs cleavage, attacks the starting compound Mn(CO)₅I giving cis‐Mn(CO)₄I(AsMe₂I) and CO. This result encouraged us to thoroughly investigate the preparation of cis‐M(CO)₄X(EMe₂Y) complexes with most of the possible combinations of M = Mn, Re; E = P, As and X, Y = Cl, Br, I. An alternative route to these compounds was opened by the cleavage of the dinuclear manganese or rhenium halides M₂(CO)₈X₂ with the halophosphanes or ‐arsanes Me₂EY. This route was found to be especially advantageous for the preparation of the rheniumcarbonyl precursors, since milder conditions than for the CO‐substitution in Re(CO)₅X compounds are sufficient for the halogen‐bridged dinuclear complexes. Cis‐M(CO)₄X(EMe₂Y) complexes were used as precursors for the synthesis of novel homo‐ and heterodinuclear complexes of the type (CO)₄M(EMe₂, X)M′(CO)₄ by reacting the EY function with transition metal carbonylates Kat[M′(CO)₅] (Kat = Na, Bu₄N, Ph₄As). Thus the preparation of a wide range of complexes was possible, which before had been successfully prepared by the direct reaction of Mn₂(CO)₁₀ with Me₂EX only in few cases, e. g. with Me₂AsI. Spectroscopic investigations, using the CO valence frequencies and the ¹H‐NMR data of the ligands EMe₂Y or of the Me₂E bridges, were applied to study the influence of the variables M, M′, E, X, Y and Kat on the reactivity of the mononuclear complexes and the bonding situation in both the mono‐ and the dinuclear systems. The new compounds were characterized by spectroscopic (IR, NMR, MS) and analytic methods (C, H).     

Formation of Isomeric Tetrathiotungstate Clusters [{Cp*Ru(CO)}2(WS4){W(CO)4}] by the Reaction of [Cp*2Ru2S4] with [W(CO)3(MeCN)3]

Thermal and photochemical interconversion occurs between the isomeric pair of tetrathiotungstate [WS₄]²⁻ clusters 1 and 2 , which were formed by thermolysis of [Cp^*₂Ru₂S₄] and [W(CO)₃(MeCN)₃] [Eq. (1)] and then structurally characterized. During synthesis, a dramatic redistribution of ligands between the Ru and W atoms takes place without the loss of any CO and S ligands.     

Organometallic Lewis Acids,Part LXII. Chiral Carbonyl‐Cyclopentadienyl‐Triphenylphosphine‐Iron and ‐Ruthenium Complexes with Tertiary Nitriles [CpM(CO)(PPh3)(N≡C–CR1R2R3)]+ BF4– (M = Fe,Ru)

A series of tertiary nitriles was synthesized by alkylation of acetonitrile, primary and secondary nitriles, using alkylbromides and sodium amide in liquid ammonia. By reaction of the in situ formed organometallic Lewis acids [CpM(CO)(PPh₃)]⁺ (M = Fe, Ru) with the novel tertiary nitriles, the complexes [CpM(CO)(PPh₃)(N≡C–CR¹R²R³]BF₄ were obtained. A di‐iron complex was formed with 1,6‐dicyanohexane.     

Eisen(II)—Phosphin-Komplexe Synthese und Kristallstrukturen von [Fe2I4(dppe)2], [Fe2(SR)4(dppe)2], [Fe(SR′)2(dppp)] und [Fe(SR)2(PMePh2)2] (dppe = Ph2P(CH2)2PPh2; dppp = Ph2P(CH2)3PPh2; R = 2,4,6-Me3C6H2; R′ = 2,4-tBuC6H3)

Iron(II) Phosphane Complexes. Synthesis and Crystal Structures of [Fe₂I₄(dppe)₂], [Fe₂(SR)₄(dppe)₂], [Fe(SR′)₂(dppp)] and [Fe(SR)₂(PMePh₂)₂] (dppe = Ph₂P(CH₂)₂PPh₂; dppp = Ph₂P(CH₂)₃PPh₂; R = 2,4,6-Me₃C₆H₂; R′ = 2,4-tBuC₆H₃) The title compounds were isolated and their structures determined by crystallographic methods. [Fe₂I₄(dppe)₂] ( 1 ) and [Fe₂(SR)₄(dppe)₂] ( 2 ) form dimeric complexes with the bidentate phosphane binding to different iron atoms. The resulting ten-membered rings of both compounds exhibit a nearly identical conformation. The central FeS₂P₂ units of the mononuclear complexes [Fe(SR′)₂(dppp)] ( 3 ) and [Fe(SR)₂(PMePh₂)₂] ( 4 ) show like 2 large deviations from ideal C_2v symmetry with bonding angles around the central iron atom ranging from 97.2, 92.5, and 96.5° (angle P? Fe? P in 2, 3 , and 4 , respectively) to 129.0, 129.9, and 133.6° (angle S? Fe? S in 2, 3 , and 4 , respectively).     

Vierkernige Clusterkomplexe vom Typ [MM′(AuPR3)2(μ‐H)(μ‐PCy2)(μ4‐PCy)(CO)6] (M,M′ = Mn,Re; R = Ph,Cy, Et): Synthese,Struktur und Topomerisierung

Tetranuclear Cluster Complexes of the Type [MM′(AuR₃)₂(μ‐H)(μ‐PCy₂)(μ₄‐PCy)(CO)₆] (M,M′ = Mn, Re; R = Ph, Cy, Et): Synthesis, Structure, and Topomerisation The dirhenium complex [Re₂(μ‐H)(μ‐PCy₂)(CO)₇(ax‐H₂PCy)] ( 1 ) reacts at room temperature in thf solution with each two equivalents of the base DBU and of ClAuPR₃ (R = Ph, Cy, Et) in a photochemical reaction process to afford the tetranuclear clusters [Re₂(AuPR₃)₂(μ‐H)(μ‐PCy₂)(μ₄‐PCy)(CO)₆] (R = Ph ( 2 ), Cy ( 3 ), Et ( 4 )) in yields of 35–48%. The homologue [Mn₂(μ‐H)(μ‐PCy₂)(CO)₇(ax‐H₂PCy)] ( 5 ) leads under the same reaction conditions to the corresponding products [Mn₂(AuPR₃)₂(μ‐H)(μ‐PCy₂)(μ₄‐PCy)(CO)₆] (R = Ph ( 6 ), Et ( 8 )). Also [MnRe(μ‐H)(μ‐PCy₂)(CO)₇(ax/eq‐H₂PCy)] ( 9 ) reacts under formation of [MnRe(AuPR₃)₂(μ‐H)(μ‐PCy₂)(μ₄‐PCy)(CO)₆] (R = Ph ( 10 ), Et ( 11 )). All new cluster complexes were identified by means of ¹H‐NMR, ³¹P‐NMR and ν(CO)‐IR spectroscopic measurements. 2 , 4 and 10 have also been characterized by single crystal X‐ray structure analyses with crystal parameters: 2 triclinic, space group P 1, a = 12.256(4) Å, b = 12.326(4) Å, c = 24.200(6) Å, α = 83.77(2)°, β = 78.43(2)°, γ = 68.76(2)°, Z = 2; 4 monoclinic, space group C2/c, a = 12.851(3) Å, b = 18.369(3) Å, c = 40.966(8) Å, β = 94.22(1)°, Z = 8; 10 triclinic, space group P 1, a = 12.083(1) Å, b = 12.185(2) Å, c = 24.017(6) Å, α = 83.49(29)°, β = 78.54(2)°, γ = 69.15(2)°, Z = 2. The trapezoid arrangement of the metal atoms in 2 and 4 show in the solid structure trans‐positioned an open and a closed Re…Au edge. In solution these edges are equivalent and, on the ³¹P NMR time scale, represent two fluxional Re–Au bonds in the course of a topomerization process. Corresponding dynamic properties were observed for the dimanganese compounds 6 and 8 but not for the related MnRe clusters 10 and 11 . 2 and 4 are the first examples of cluster compounds with a permanent Re–Au bond valence isomerization.     

Heterodinukleare Komplexe: Synthese und Kristallstrukturen von [RuRh(μ‐CO)(CO)4(μ‐PtBu2)(tBu2PH)], [RuRh(μ‐CO)(CO)3(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] und [CoRh(CO)4(μ‐H)(μ‐PtBu2)(tBu2PH)]

Heterobinuclear Complexes: Synthesis and X‐ray Crystal Structures of [RuRh(μ‐CO)(CO)₄(μ‐P^tBu₂)(^tBu₂PH)], [RuRh(μ‐CO)(CO)₃(μ‐P^tBu₂)(μ‐Ph₂PCH₂PPh₂)], and [CoRh(CO)₄(μ‐H)(μ‐P^tBu₂)(^tBu₂PH)] [Ru₃Rh(CO)₇(μ₃‐H)(μ‐P^tBu₂)₂(^tBu₂PH)(μ‐Cl)₂] ( 2 ) yields by cluster degradation under CO pressure as main product the heterobinuclear complex [RuRh(μ‐CO)(CO)₄(μ‐P^tBu₂)(^tBu₂PH)] ( 4 ). The compound crystallizes in the orthorhombic space group Pcab with a = 15.6802(15), b = 28.953(3), c = 11.8419(19) Å and V = 5376.2(11) ų. The reaction of 4 with dppm (Ph₂PCH₂PPh₂) in THF at room temperature affords in good yields [RuRh(μ‐CO)(CO)₃(μ‐P^tBu₂)(μ‐dppm)] ( 7 ). 7 crystallizes in the triclinic space group P 1 with a = 9.7503(19), b = 13.399(3), c = 15.823(3) Å and V = 1854.6 ų. Moreover single crystals of [CoRh(CO)₄(μ‐H)(μ‐P^tBu₂)(^tBu₂PH)] ( 9 ) could be obtained and the single‐crystal X‐ray structure analysis revealed that 9 crystallizes in the monoclinic space group P2₁/a with a = 11.611(2), b = 13.333(2), c = 18.186(3) Å and V = 2693.0(8) ų.     

Synthese und Struktur chiraler Heterometallatetrahedrane des Typs [Re2(M1PPh3)(M2PPh3)(μ‐PCy2)(CO)7C≡CPh] (M1 = Ag,Au; M2 = Cu,Ag, Au)

Syntheses and Structure of Chiral Metallatetrahedron Complexes of the Type [Re₂(M¹PPh₃)(M²PPh₃)(μ‐PCy₂)(CO)₇C≡CPh] (M¹ = Ag, Au; M² = Cu, Ag, Au) From the reaction of Li[Re₂(μ‐H)(μ‐PCy₂)(CO)₇(C(Ph)O)] ( 1 ) with Ph₃AuC≡CPh both benzaldehyde and the trinuclear complex Li[Re₂(AuPPh₃)(μ‐PCy₂)(CO)₇C≡CPh] ( 2a ) were obtained in high yield. The complex anion was isolated as its PPh₄‐salt 2b . The latter reacts with coinage metal complexes PPh₃M²Cl [M² = Cu, Ag, Au] to give chiral heterometallatetrahedranes of the general formula [Re₂(AuPPh₃)(M²PPh₃)(μ‐PCy₂)(CO)₇C≡CPh] (M² = Cu 3a , Ag 3b , Au 3c ). The corresponding complex [Re₂(AgPPh₃)₂(μ‐PCy₂)(CO)₇C≡CPh] ( 3d ) is obtained from the reaction of [Re₂(AgPPh₃)₂(μ‐PCy₂)(CO)₇Cl] ( 4 ) with LiC≡CPh. 3d undergoes a metathesis reaction in the presence of PPh₃CuCl giving [Re₂(AgPPh₃)(CuPPh₃)(μ‐PCy₂)(CO)₇C≡CPh] ( 3e ) and PPh₃AgCl. Analogous metathesis reactions are observed when 3c is reacted with PPh₃AgCl or PPh₃CuCl giving 3a or 3b , respectively. The reaction of 1 with PPh₃AuCl gives benzaldehyde and Li[Re₂(AuPPh₃)(μ‐PCy₂)(CO)₇Cl] ( 5a ) which upon reaction with PhLi forms the trinuclear complex Li[Re₂(AuPPh₃)(μ‐PCy₂)(CO)₇Ph] ( 6a ). Again this complex was isolated as its PPh₄‐salt 6b . In contrast to 2b , 6b reacts with one equivalent of Ph₃PAuCl by transmetalation to give Ph₃PAuPh and PPh₄[Re₂(AuPPh₃)(μ‐PCy₂)(CO)₇Cl] ( 5b ). The X‐ray structures of the compounds 3a , 3b , 3e and 4 are reported.     

Chalkogen‐Derivate der Halbsandwich‐Wolfram(V)‐Komplexe Cp*WCl4 und Cp*WCl4(PMe3). Röntgen‐Kristallstrukturanalysen von anti‐[Cp*W(Se)(μ‐Se)]2 und Cp*W(S)2(OMe)

Chalcogen Derivatives of the Halfsandwich Tungsten(V) Complexes Cp*WCl₄ and Cp*WCl₄(PMe₃). X‐Ray Crystal Structure Analyses of anti ‐[Cp*W(Se)(μ‐Se)]₂ and Cp*W(S)₂(OMe) The chalcogenation of Cp*WCl₄ ( 1 ) by E(SiMe₃)₂ (E = S, Se) and Te(SiMe₂^tBu)₂ in chloroform solution leads to dimeric products of the type anti‐[Cp*W(E)(μ‐E)]₂ (E = S ( 3 a ), Se ( 3 b ) and Te ( 3 c )). An X‐ray structure determination of 3 b indicates a centrosymmetric molecule containing a planar W(μ‐Se)₂W ring, the W–W distance (297.9(1) pm) corresponds to a single bond. In the presence of air the two terminal chalcogenido ligands (E) in 3 a – c are stepwise replaced by oxido ligands (O) to give [Cp*W(O)(μ‐E)]₂ (E = S ( 5 a ), Se ( 5 b ) and Te ( 5 c )) in quantitative yields. The reaction of Cp*WCl₄ with H₂S or ammonium polysulfide, (NH₄)₂S_x (x ∼ 10), leads to Cp*W(S)₂Cl ( 6 a ); the corresponding methoxy derivative, Cp*W(S)₂OCH₃ ( 9 a ), has been characterized by an X‐ray structure analysis. On the other hand, the reaction of Cp*WCl₄(PMe₃) ( 2 ) with sodium tetrasulfide, Na₂S₄, in dimethylformamide solution gives a mixture of mononuclear Cp*W(S)(S₂)Cl ( 8 a ), dinuclear [Cp*W(S)(μ‐S)]₂ ( 3 a ) and a trinuclear side‐product of composition Cp*₂W₃S₇ ( 13 a ). Terminal sulfido ligands are replaced by terminal oxido ligands in solution in the presence of oxygen. Thus, 6 a is stepwise converted into Cp*W(O)(S)Cl ( 10 a ) and CpW(O)₂Cl ( 12 a ), whereas 8 a gives Cp*W(O)(S₂)Cl ( 11 a ) and 13 a leads to Cp*₂W₃(O)S₆ ( 14 a ). The disulfido complexes 8 a and 11 a are desulfurized by triphenylphosphane to give 6 a and 10 a . The new complexes have been characterized by their IR and NMR spectra and by mass spectrometry.     

Some complexes containing carbon chains end-capped by M(CO)2Tp′ [M = Mo, W; Tp′ = HB(pz)3, HB(dmpz)3] groups

Complexes M(CCCSiMe₃)(CO)₂Tp′ (Tp′ = Tp [HB(pz)₃], M = Mo 2, W 4; Tp′ = Tp^∗ [HB(dmpz)₃], M = Mo 3) are obtained from M(CCCSiMe₃)(O₂CCF₃)(CO)₂(tmeda) (1) and K[Tp′].Reactions of 2 or 4 with AuCl(PPh₃)/K₂CO₃ in MeOH afforded M{CCCAu(PPh₃)}(CO)₂Tp′ (M = Mo 5, W 6) containing C₃ chains linking the Group 6 metal and gold centres.In turn, the gold complexes react with Co₃(μ₃-CBr)(μ-dppm)(CO)₇ to give the C₄-bridged {Tp(OC)₂M}CCCC{Co₃(μ-dppm)(CO)₇} (M = Mo 7, W 8), while Mo(CBr)(CO)₂Tp^∗ and Co₃{μ₃-C(CC)₂Au(PPh₃)}(μ-dppm)(CO)₇ give {Tp^∗(OC)₂Mo}C(CC)₂C{Co₃(μ-dppm)(CO)₇} (9) via a phosphine-gold(I) halide elimination reaction. The C₃ complexes Tp′(OC)₂MCCCRu(dppe)Cp^∗ (Tp′ = Tp, M = Mo 10, W 11; Tp′ = Tp^∗, M = Mo 12) were obtained from 2-4 and RuCl(dppe)Cp^∗ via KF-induced metalla-desilylation reactions. Reactions between Mo(CBr)(CO)₂Tp^∗ and Ru{(CC)_nAu(PPh₃)}(dppe)Cp^∗ (n = 2, 3) afforded {Tp^∗(OC)₂Mo}C(CC)_n{Ru(dppe)Cp^∗} (n = 2 13, 3 14), containing C₅ and C₇ chains, respectively. Single-crystal X-ray structure determinations of 1, 2, 7, 8, 9 and 12 are reported.     

{1,1′‐(Dimethylsilylene)bis[methanechalcogenolato]}diiron Complexes [2Fe2E(Si)] (E=S,Se, Te) – [FeFe] Hydrogenase Models

(Bis‐selenolato) and (bis‐tellurolato)diiron complexes [2Fe2E(Si)] were prepared and compared with the known (bis‐thiolato)diiron complex A to assess their ability to produce hydrogen from protons. Treatment of [Fe₃(CO)₁₂] with 4,4‐dimethyl‐1,2,4‐diselenasilolane ( 1 ) in boiling toluene afforded hexacarbonyl{μ‐{[1,1′‐(dimethylsilylene)bis[methaneselenolato‐κSe : κSe]](2 ?)}}diiron(Fe? Fe) ( 2 ). The analog bis‐tellurolato complex hexacarbonyl{μ‐{[1,1′‐(dimethylsilylene)bis[methanetellurolato‐κTe : κTe]](2 ?)}}diiron(Fe? Fe) ( 3 ) was obtained by treatment of [Fe₃(CO)₁₂] with dimethylbis(tellurocyanatomethyl)dimethylsilane, which was prepared in situ. All compounds were characterized by NMR, IR spectroscopy, mass spectrometry, elemental analysis and single‐crystal X‐ray analysis. The electrocatalytic properties of the [2Fe2X(Si)] (X=S, Se, Te) model complexes A, 1 , and 2 towards hydrogen formation were evaluated.     

[μ‐(Me3SiCH2Sb)5–Sb1,Sb3–{W(CO)5}2] und [{(Me3Si)2CHSb}3Fe(CO)4] – zwei cyclische Komplexe mit Antimon‐Liganden

Syntheses and Crystal Structures of [μ‐(Me₃SiCH₂Sb)₅–Sb¹,Sb³–{W(CO)₅}₂] and [{(Me₃Si)₂CHSb}₃Fe(CO)₄] – Two Cyclic Complexes with Antimony Ligands cyclo‐(Me₃SiCH₂Sb)₅ reacts with [(THF)W(CO)₅] (THF = tetrahydrofuran) to form cyclo‐[μ‐(Me₃SiCH₂Sb)₅–Sb¹,Sb³–{W(CO)₅}₂] ( 1 ). The heterocycle cyclo‐ [{(Me₃Si)₂CHSb}₃Fe(CO)₄] ( 2 ) is formed by an insertion reaction of cyclo‐[(Me₃Si)₂CHSb]₃ and [Fe₂(CO)₉]. The crystal structures of 1 and 2 are reported.