Bis(cyclopentadienyl)methan-verbrückte Zweikernkomplexe. VIII. Zweikernige Cobaltkomplexe mit dem Dianion des Bis(cyclopentadienyl)methans und des Bis(tetramethylcyclopentadienyl)dimethylsilans als Brückenliganden

Bis(cyclopentadienyl)methane-bridged Dinuclear Complexes. VIII. Dinuclear Cobalt Complexes with the Dianion of Bis(cyclopentadienyl)methane and Bis(tetramethylcyclopentadienyl)dimethylsilane as Bridging Ligands The dinuclear cobalt complex [CH₂(C₅H₄)₂][Co(CO)₂]₂ ( 4 ) which is obtained from [Co(CO)₄I] ( 2 ) and Li₂[CH₂(C₅H₄)₂] ( 3 ) in 75% yield reacts with PMe₃, PiPr₃, P₂Me₄, Me₂PCH₂CH₂PMe₂ and (EtO)₂POP(OEt)₂, to the compounds 5–9 substituting one CO ligand per cobalt atom. Oxidative addition of CH₃I to [CH₂(C₅H₄)₂][Co(CO)(PMe₃)]₂ ( 5 ) leads to the formation of the dinuclear cobalt(III) complex [CH₂(C₅H₄)₂][Co(COCH₃)(PMe₃)I]₂ ( 11 ). The reaction of 4 with iodide generates [CH₂(C₅H₄)₂][Co(CO)I₂]₂ ( 12 ) which with PMe₃, P(OMe)₃, P(OiPr)₃, and CNMe reacts under CO substitution to [CH₂(C₅H₄)₂][Co(L)I₂]₂ ( 13–16 ) and with PMe₂H to {[CH₂(C₅H₄)₂][Co(PMe₂H)₃]₂}I₄ ( 17 ). The electrophilic addition reactions of NH₄PF₆ and CH₃I to [CH₂(C₅H₄)₂][Co(PMe₃)₂]₂ ( 20 ) produce the complex salts {[CH₂(C₅H₄)₂][CoR(PMe₃)₂]₂}X₂ ( 21 : R = H; 22 : R = CH₃). From 22a (X = I) and LiCH₃ the dinuclear tetramethyldicobalt compound [CH₂(C₅H₄)₂] · [Co(CH₃)₂(PMe₃)]₂ ( 23 ) is obtained which further reacts, via the intermediate 24 , to the chiral complex {[CH₂(C₅H₄)₂] · [CoCH₃(PMe₃)P(OMe)₃]₂}(PF₆)₂ ( 25 ). The reaction of 20 with C₂(CN)₄ and E- or Z-C₂H₂(CO₂Me)₂ gives the olefin(trimethylphosphine) cobalt(I) derivatives 26 und 27 . The synthesis of the dinuclear compounds 31–38 with [Me₂Si(C₅Me₄)₂]^2? as the bridging unit is also described.     

Basische metalle : XXXVI. Die synthese stabiler hydrido(olefin)rhodium-komplexe und von[C5H5Rh(PMe3)(η3-CH3CHC6H5)]PF6

The complexes C₅H₅Rh(PMe₃)C₂H₃R′ (R′  H, Me, Ph) and C₅H₅Rh(PR₃)C₂H₄(PR₃  PMe₂Ph, PPrⁱ₃) are prepared by reaction of[PMe₃(C₂H₃R/t')RhCl]₂ or [PR₃(C₂H₄)RhCl]₂ and TlC₅H₅, respectively. They react with HBF₄ in ether/propionic anhydride to form the BF₄ salts of the hydrido(olefin)rhodium cations [C₅H₅RhH(C₂H₃R′)PR₃]⁺(R  Me; R′  H, Me and R  Prⁱ; R′  H). From C₅H₅Rh(PMe₃)C₂H₃Ph and CF₃COOH/NH₄PF₆ the η³-benzyl complex [C₅H₅Rh(PMe₃)(η³-CH₃CHC₆H₅)]PF₆ is obtained. The reversibility of the protonation reactions is demonstrated by temperature-dependent NMR spectra and by deuteration experiments. The complexes C₅H₅Rh(PMe₃)C₂H₃R′ (R′  H, Ph) and C₅H₅Rh(PMe₂Ph)C₂H₄ react with CH₃I in ether to give the salts [C₅H₅RhCH₃(C₂H₃R′)PR₃]I which in THF or CH₃NO₂ yield the neutral compounds C₅H₅RhCH₃(PR₃)I.     

Metallkomplexe mit verbrückenden dimethylphosphidoliganden: VI. Zweikernkomplexe mit substituierten vinyldimethylphosphan-brückenliganden durch templatsynthese aus [(C5H5Co)2(μ-PMe2)2(μ-H)]+ und alkinen. Die kristallstruktur von [(C5H5Co)2(μ-PMe2)(μ-η4-Me2PC(CO2Me)CHC(OMe)O)]BF4

The hydrido-bridged dinuclear complex [(C₅H₅CO)₂(μ-PMe₂)₂(μ-H)]BF₄ (I) reacts with C₂(CO₂Me)₂ to produce a mixture of (C₅H₅Co)₂[μ-η⁴-Me₂PC(CO₂Me)C(CO₂Me)PMe₂] (II) and [(C₅H₅Co)₂(μ-PMe₂)(μ-η⁴-Me₂PC(CO₂Me)-CHC(OMe)O)]BF₄ (III). The X-ray structural analysis of III reveals that besides a dimethylphosphido bridge the cation contains a substituted vinyldimethylphosphine ligand which behaves as a 6-electron donor group and is coordinated via phosphorus and oxygen to the first cobalt and via the CC bond the second cobalt atom. The reactions of I with HC₂CO₂Me and CH₃C₂CO₂Me also give mixtures of products which contain the neutral component, (C₅H₅Co)₂[μ-η⁴-Me₂PCRC(CO₂Me)PMe₂] (IV: R  H; VII: R  CH₃), i.e., the structural analogue of II. The ionic products V, VI (obtained from HC₂CO₂Me) and VIII, IX (obtained from CH₃C₂CO₂Me) have been characterized by IR and NMR spectroscopy. {(C₅H₅Co)₂[μ-η⁴-PMe₂C(CH₃)C(CO₂Me)PMe₂](μ-H)}BF₄ (VIII) has independently been prepared by treatment of VII with HBF₄.     

Basische metalle: LII. Synthese von carbenoid- und ylidcobalt(III)-komplexen aus substitutionslabilen cobalt(I)-vorstufen

The cyclopentadienylcobalt(I) compounds C₅H₅Co(PMe₃)P(OR)₃ (R = Me, Et, Prⁱ) and C₅H₅Co(C₂H₄)L (L = PMe₃, P(OMe)₃, CO) are prepared by ligand substitution starting from C₅H₅Co(PMe₃)₂ and C₅H₅Co(C₂H₄)₂. Whereas the reaction of C₅H₅Co(PMe₃)P(OMe)₃ with CH₂Br₂ mainly gives [C₅H₅CoBr(PMe₃)P(OMe)₃]Br, the dihalogenocobalt(III) complexes C₅H₅CoX₂(PMe₃) (X = Br, I) are obtained from C₅H₅Co(CO)PMe₃ and CH₂X₂. Treatment of C₅H₅Co(CO)PMe₃ or C₅H₅Co(C₂H₄)PMe₃ with CH₂ClI at low temperatures produces a mixture of C₅H₅CoCH₂Cl(PMe₃)I and C₅H₅CoCl(PMe₃)I, which can be separated due to their different solubilities. The same reaction in the presence of ligand L gives the carbenoidcobalt(III) compounds [C₅H₅CoCH₂Cl(PMe₃)L]PF₆ in nearly quantitative yields. If NEt₃ is used as the Lewis base, the ylide complexes [C₅H₅Co(CH₂PMe₃)(PMe₃)X]PF₆ (X = Br, I) are obtained. The PF₆ salts of the dications [C₅H₅Co(CH₂PMe₃)(PMe₃)L]²⁺ (L = PMe₃, P(OMe)₃, CNMe) and [C₅H₅Co(CH₂PMe₃)(P(OMe)₃)₂]²⁺ are prepared either from [C₅H₅Co(CH₂PMe₃)(PMe₃)X]⁺ and L, or more directly from C₅H₅Co(CO)PMe₃, CH₂X₂ and PMe₃ or P(OMe)₃, respectively. The synthesis of C₅H₅CoCH₂OMe(PMe₃)I is also described.     

Komplexe mit kohlenstoffsulfiden und -seleniden als liganden: XIII. Reaktionen der metall-basen C5H5M(PR3)2 und C5H5M(PR3)L (M = Co,Rh) mit CSSe und CSe2: synthese und eigenschaften von cyclopentadienylcobalt- und rhodium- komplexen mit CS,CSe, CSSe,CSe2, CSSe22−, CSe32−, C2S2Se22−- und C2Se42−- als liganden

C₅H₅Co(PMe₃)₂ (I) reacts with CSSe to give C₅H₅Co(η²-CSSe)PMe₃ (IV) and C₅H₅Co(CS)PMe₃ (V). The thiocarbonyl complex V is formed in an almost quantitative yield by Se abstraction from IV and PPh₃. The corresponding compounds C₅H₅Co(CS)PMe₂Ph (VII) and C₅H₅Co(CS)[P(OMe)₃] (VIII) are obtained as the main products directly from CSSe and C₅H₅Co(PMe₂Ph)₂ or C₅H₅Co[P(OMe)₃]₂. In the reaction of C₅H₅Co(PR₃)₂ (PR₃ = PMe₃, PMe₂Ph) with CSe₂, the carbon diselenide complexes C₅H₅Co(η²-CSe₂)PMe₃ (XI) and C₅H₅Co(η²-CSe₂)PMe₂Ph (XIV) are formed. XI reacts with PPh₃ to give C₅H₅Co(CSe)PMe₃ (XII). Cyclopentadienylcobalt compounds containing CSSe₂^2?, CSe₃^2? and C₂Se₄^2? as ligands are isolated as side products in the; reactions of C₅H₅Co(PR₃)₂ and C₅H₅Co(CO)PR₃ (PR₃ = PMe₃, PMe₂Ph) with CSSe and CSe₂, respectively. Displacement of ethylene from C₅H₅Rh(C₂H₄)PMe₃ by CSSe yields the complex C₅H₅Rh(η²-CSSe)PMe₃ (XVIII) which reacts with PPh₃ to give C₅H₅Rh(CS)PMe₃ (XIX) and with excess CSSe to give C₅H₅RhC₂S₂Se₂(PMe₃) (XX). Besides small amounts of C₅H₅Rh(η²CSSe)PMe₂Ph (XXI), the corresponding metallaheterocycle C₅H₅RhC₂S₂Se₂(PMe₂Ph) (XXII) is formed as the main product from C₅H₅Rh(C₂H₄)PMe₂Ph and CSSe.     

Bis(cyclopentadienyl)methan-verbrückte Zweikernkomplexe: II. Synthese und Reaktionen ringverbrückter Cobalt-Zweikernkomplexe mit zwei nucleophilen Metallzentren

The dinuclear cobalt complex [CH₂(C₅H₄)₂][Co(PMe₃)₂]₂ (2), which is prepared from CoCl(PMe₃)₃ and [CH₂(C₅H₄)₂]Li₂, reacts with NH₄PF₆ and CH₃I to form the protonated and methylated dications {[CH₂(C₅H₄)₂][CoR(PMe₃)₂]₂}²⁺ (R = H, CH₃). Treatment of {[CH₂(C₅H₄)₂][CoCH₃(PMe₃)₂]₂}I₂ (4) with LiCH₃ affords the neutral compound [CH₂(C₅H₄)₂][Co(CH₃)₂(PMe₃)]₂ (5). Ligand substitution of [CH₂(C₅H₄)₂][Co(CO)₂]₂ (6) with P₂Me₄ and 1,2-C₂H₄(PMe₂)₂(dmpe) gives the doubly-bridged complexes [CH₂(C₅H₄)₂][Co₂(CO)₂(μ-P₂Me₄)] (7) and [CH₂(C₅H₄)₂][Co₂(CO)₂(μ-dmpe)] (8), respectively. Similarly, [CH₂(C₅H₄)₂][Co-(CO)(PMe₃)]₂ (9) is obtained from the reaction of 6 with PMe₃. Oxidation of 6 with iodine gives [CH₂(C₅H₄)₂][Co(CO)I₂]₂ (11) which is transformed via {[CH₂(C₅H₄)₂][Co(PMe₂H)₃]₂}I₄ (12) into the triply-bridged cobalt(II) complex [CH₂(C₅H₄)₂][CO₂(μ-PMe₂)₂] (13).     

Basische Metalle. XIV. Synthese und Kristallstruktur von C5H5(PMe3)CoS5: Ein neuer Metallapentathia-Heterocyclus

Basic Metals. XIV. Synthesis and Crystal Structure of C₅H₅(PMe₃)CoS₅: A New Metallapentathia Heterocycle The dinuclear complex C₅H₅(PMe₃)Co(μ-CO)₂Mn(CO)C₅H₄Me ( 3 ) reacts with stoi-chiometric amounts of S₈ to form C₅H₅(PMe₃)CoS₅ ( 4 ) in practically quantitative yields. The cobalt-apentathia heterocycle 4 is also obtained by the reaction of C₅H₅(PMe₃)Co(h²-CS₂) ( 5 ) with S₈. Crystals of 4 are monoclinio with a = 8.467(3) Å, b = 12.128(4) Å, c = 14.210(4) Å and Å = 102.20(2)°. The chair form of the six-membered CoS₅ ring corresponds to that of the compounds (C₅H₅)₂TiS₅ and (C₅H₅)₂VS₅. In 4 , the cyclopentadienyl ligand occupies the axial and the trimethylphosphine group the equatorial position.     

Basische metalle : XXXVII. Zur reaktivität der ethylen(hydrido)rhodium-komplexe [C5H5RhH(C2H4)PR3]X gegenüber nucleophilen: insertion versus substitution

The complex [C₅H₅RhH(C₂H₄)PMe₃]BF₄ (I) reacts with NaF and NaCN by deprotonation to give C₅H₅Rh(PMe₃)C₂H₄ but with NaCl, NaBr and NaI the ethylrhodium compounds C₅H₅RhC₂H₅(PMe₃)X (II–IV) are obtained. The reactions of I with CO and PPrⁱ₃ yield the BF₄ salts of the cations [C₅H₅RhH(CO)PMe₃]⁺ and [C₅H₅RhH(PPrⁱ₃)PMe₃]⁺ (V, VI), respectively, from which the uncharged complexes C₅H₅Rh(CO)PMe₃ (VII) and C₅H₅Rh(PPRⁱ₃)PMe₃ (VIII) are prepared. The carbonyl compound VII is also accessible either from C₅H₅Rh(CO)₂ and PMe₃ or from C₅H₅Rh(PMe₃)₂ and CO. The reaction of I with ethylene leads to the BF₄ salt of the cation [C₅H₅RhC₂H₅(PMe₃)C₂H₄]⁺ (X) which on treatment with PMe₃ forms the complex [C₅H₅RhC₂H₅(PMe₃)C₂H₄PMe₃]BF₄ (XI). The compound [C₅H₅RhH(C₂H₄)PPrⁱ₃]BF₄ (XII) reacts with NaI by insertion to yield C₅H₅RhC₂H₅(PPrⁱ₃)I (XIII) whereas with PPrⁱ₃ the salt [C₅H₅RhH(PPrⁱ₃)₂]BF₄ (XIV) is produced. The bis(triisopropylphosphine) complex C₅H₅Rh(PPrⁱ₃)₂ (XVI) is obtained from XIV and NaH.     

Vielseitige Koordinationschemie von Vanadium(V): Substitutionsreaktionen,Umlagerungen und Kondensationsreaktionen von Oxovanadium(V)‐Komplexen des tripodalen Sauerstoffliganden LOMe− = [η5‐(C5H5)Co{P(OMe)2(O)}3]−

Multifaceted Coordination Chemistry of Vanadium(V): Substitution, Rearrangement Reactions, and Condensation Reactions of Oxovanadium(V) Complexes of the Tripodal Oxygen Ligand L_OMe^? = [η⁵‐(C₅H₅)Co{P(OMe)₂(O)}₃]^? The octahedral oxovanadium(V) complex [V(O)F₂L_OMe] of the tripodal oxygen ligand L_OMe^? = [η⁵‐(C₅H₅)Co{P(OMe)₂(O)}₃]^? reacts with alcohols and phenol with substitution of one fluoride ligand to form alkoxo complexes [V(O)F(OR)L_OMe], R = Me, Et, i‐Prop, Ph. In the presence of water, however, both fluoride ions are substituted and a complex with the composition VO₂L_OMe can be isolated. The crystal structure shows that the oxo‐bridged trimer [{V(O)(L_OMe)O}₃] was synthesized. In the presence of BF₃ the fluoride ligand in the alkoxo‐complex [V(O)F(OEt)L_OMe] can be exchanged for pyridine to yield [V(O)(OEt)pyL_OMe]BF₄. Analogous attempts to exchange the fluoride ligand for tetrahydrofuran and acetonitrile induces a rearrangement reaction that leads to the vanadium complex [V(O)(L_OMe)₂]BF₄. The crystal structure of this compound has been determined. Its ¹H and ³¹P‐NMR spectra show that it is a highly fluxional vanadium complex at ambient temperature in solution. The two tripodal ligands L_OMe^? coordinate the vanadium centre as bidentate or tridentate ligands. The exchange bidentate/tridentate becomes slow on the NMR time scale below about 200 K.     

Reaktion des hydridodicobalt-kations [(C5H5Co)2(μ-PMe2)2(μ-H)]+ mit C2(CO2Me)2: Bildung und kristallstruktur eines zweikernkomplexes mit O=C(OMe)CH=C(CO2Me)PMe2 als 6-elektronen-donorligand

[(C₅H₅Co)₂(μ-PMe₂)₂(μ-H)]BF₄ ([II]BF₄) reacts with C₂(CO₂Me)₂ to give the products III and IV. The ionic compound III which formally is a $\text{1}\text{1}$ adduct of [II]BF₄ and C₂(CO₂Me)₂ has been characterized by X-ray structure analysis. III contains the group O=C(OMe)CH=C(CO₂Me)PMe₂ as a 6-electron donor ligand chelated to a cobalt atom and π-bonded to the other cobalt atom. Complex IV is a neutral compound which also can be obtained from [C₅H₅Co(μ-PMe₂)]₂ (I) and C₂(CO₂Me)₂.     

Synthesis and reactions of a nucleophilic bis(μ-dimethylphosphido)dicobalt complex. The crystal and molecular structure of [C5H5Co(μ-PMe2)]2 and [(C5H5Co)2(μ-H)(μ-PMe2)2]BPh4

The bis(μ-dimethylphosphido)dicobalt complex [C₅H₅Co(μ-PMe₂)]₂ (II) has been prepared from Co(C₅H₅ and PMe₂H on almost quantitative yield. It has also been made by reduction of [C₅H₅Co(PMe₂H)₃]I₂ (IV) with NaH and from the reaction of [C₅H₅(PMe₃)Co(μ-CO)₂Mn(CO)C₅H₄Me] with PMe₂H. Protonation of II with CF₃CO₃H in the presence of NH₄PF₆ produces the PF₆^? salt of the (μ-hydrido)dicobalt cation [(C₅H₅Co)₂(μ-H)(μ-PMe₂)₂]⁺ (V) which reacts with aqueous NaOH to give II. Similar treatment of [C₅H₅Co(μ-SMe]₂ with CF₃CO₂H/NH₄PF₆ leads to the formation of [(C₅H₅Co)₂(μ-SMe)₃]PF₆ (VI). The nucleophilic character of complex II has also been demonstrated in the reaction with SO₂, which gives [(C₅H₅Co)₂ (μ-PMe₂)₂(μ-SO₂)] (VII). The crystal and molecular structures of II, the corresponding bis(μ-diphenylphosphido) compound [C₅H₅Co(μ-PPh₂)]₂ (III) and the BPh₄^? salt of V have been determined. In both neutral complexes the Co₂P₂ cores are similarly puckered, as reflected in the dihedral angle between the CoP₂ and P₂Co′ planes of 108.1 and 105.0° for R = Me and Ph, respectively. The CoCo bond length and the PP interatomic separations are essentially identical for both dimers. The CoCo bond length in V, 2.517(1) Å, is lower than that in II, 2.542(2) Å. The only obvious structural variation between the unprotonated and the protonated species is the large difference in the degree of canting of the C₅H₅ rings with respect to each other. The angles between the C₅(ring)-centroid and the CoCo line are ca. 150 and 167° in II and V, respectively, which reflects the influence of the bridging hydride ligand in the cationic complex.     

Mono-η-arenebis(trimethylphosphine(rhenium chemistry: alkyl,hydrido, halogeno and olefin derivatives

Co-condensation of rhenium atoms with a benzene-trimethylphosphine mixture gives the dimer [Re(ν-C₆H₆)(PMe₃)₂]₂ which is a precursor to the new compounds Re(η-C₆H₆)(PMe₃)₂R (R = H, Cl, I, Me, Et, CHCH₂ or Ph), [Re(η-C₆H₆)(PMe₃)₂X₂]BF₄ (X₂ = H₂ or HI), [Re(η-C₆H₆)(PMe₃)₂H₂][BF₄]₂, and [Re(η-C₆H₆)(PMe₃)₂L]BF₄ (L = η-C₂H₄ or CO). Co-condensation of manganese atoms with benzene-trimethylphosphine gives Mn(η-C₆H₆)(PMe₃)₂H.     

Diene and dienyl complexes of transition elements: VII. Carbonylchlorobis(dimethylphenylphosphine)-(η3-pentadienyl)ruthenium

The reaction between [{Ru(CO)Cl₂(PMe₂Ph)₂}₂] and SnBu₃(C₅H₇) in chloroform yields the η³-pentadienyl complex [Ru(CO)Cl(η³-C₅H₇)(PMe₂Ph)₂]. The ¹H NMR spectra are reported and discussed.     

Electron‐Rich Diferrous–Phosphane–Thiolates Relevant to Fe‐only Hydrogenase: Is Cyanide “Nature's Trimethylphosphane”?

The two‐step one‐pot oxidative decarbonylation of [Fe₂(S₂C₂H₄)(CO)₄(PMe₃)₂] ( 1 ) with [FeCp₂]PF₆, followed by addition of phosphane ligands, led to a series of diferrous dithiolato carbonyls 2 – 6 , containing three or four phosphane ligands. In situ measurements indicate efficient formation of 1 ²⁺ as the initial intermediate of the oxidation of 1 , even when a deficiency of the oxidant was employed. Subsequent addition of PR₃ gave rise to [Fe₂(S₂C₂H₄)(μ‐CO)(CO)₃(PMe₃)₃]²⁺ ( 2 ) and [Fe₂(S₂C₂H₄)(μ‐CO)(CO)₂(PMe₃)₂(PR₃)₂]²⁺ (R=Me 3 , OMe 4 ) as principal products. One terminal CO ligand in these complexes was readily substituted by MeCN, and [Fe₂(S₂C₂H₄)(μ‐CO)(CO)₂(PMe₃)₃(MeCN)]²⁺ ( 5 ) and [Fe₂(S₂C₂H₄)(μ‐CO)(CO)(PMe₃)₄(MeCN)]²⁺ ( 6 ) were fully characterized. Relevant to the H_red state of the active site of Fe‐only hydrogenases, the unsymmetrical derivatives 5 and 6 feature a semibridging CO ligand trans to a labile coordination site.     

Synthesis of a vinylcarbynetetrairon complex. Crystal and molecular structure of [(C5H5)2(CO)2Fe2(μ-CO)]2- (μ-C5H3)+BF4−

The diiron vinyl ether carbyne complex [(C₅H₅)(CO)Fe]₂(μ-CO)- (μ-CCHCHOCH₂CH₃)⁺ BF₄⁻ (1) reacted with the diiron ethenylidene complex [(C₅H₅)(CO)Fe]₂(μ-CO)(μ-CCH₂) (2) to yield the tetrairon complex [(C₅H₅)₂(CO)₂Fe₂(μ-CO)]₂(μ-C₅H₃⁺BF₄⁻ (3) which was characterized by spectroscopy and by single crystal X-ray diffraction.     

Basische metalle: LVI. Synthese von Li2[(C5Me4)2CH2] und ringverbrückter rhodium-zweikernkomplexe mit dem (C5Me4)2CH2-dianion als brückenliganden

Li₂[(C₅Me₄)₂CH₂] (III), the dilithium salt of the novel permethylated ring-connected [(C₅Me₄)₂CH₂]²⁻ dianion, has been prepared from C₅Me₄H₂ (I) via (C₅Me₄H)₂CH₂ (II) and subsequent reaction with n-BuLi. III reacts with [Rh(C₂H₄)(PMe₃)Cl]₂ to give the dinuclear complex [(C₅Me₄)₂CH₂][Rh(C₂H₄)PMe₃]₂ (IV) from which on methylation the compounds {[(C₅Me₄)₂CH₂][RhCH₃(C₂H₄)PMe₃]₂} (PF₆)₂ (V) and [(C₅Me₄)₂CH₂][RhCH₃(PMe₃)I]₂ (VI) are obtained. Treatment of IV with excess trifluoroacetic acid leads to the formation of [(C₅Me₄)₂CH₂](Rh(PMe₃)(OCOCF₃)₂]₂ (VII) which reacts with chelating diphosphines in the presence of NH₄PF₆ to give the PF₆ salts of the doubly-bridged dications {[(C₅Me₄)₂CH₂][Rh₂(PMe₃)₂(OCOCF₃)₂(μ-P-P)]}²⁺ (PP = dppm, dppe, dppb) (IX–XI). The reaction of III with [Rh(CO)₂Cl]₂ produces a mixture of the dinuclear complexes [(C₅Me₄)₂CH₂][Rh(CO)₂]₂ (XII) and [(C₅Me₄)₂CH₂][Rh₂(μ-CO)₂] (XIII) which are easily interconverted under mild conditions.     

Übergangsmetall-heteroallen-komplexe: XIII. Reaktionen der cobalt-thioketen-komplexe [Co(R2CCS)(C5H5)] mit elektrophilen

Reaction of the η²(C,S)-coordinated thioketene cobalt complex [Co(C₁₁H₁₈S)-(PMe₃(C₅H₅)] (2a) with the electrophils [Mn(CO)₂(THF)(C₅H₅] and [Cr(CO)₅(THF)] gives the dinuclear thioketene complexes (4) with two different metal atoms in the molecule. The structure of the cobalt manganese compound was determined by X-ray diffraction. Protonation of the mononuclear thioketene complexes 2 give novel cationic η²-bonded thioacyl compounds [Co(η²-RCS)-(PMe₃(C₅H₅)]⁺ (9), as confirmed by X-ray analysis.     

Basische metalle: LIII. Ruthenium- und osmium-komplexe mit dem dimethylphosphinomethanid-anion als liganden

The reduction of trans-RuCl₂(PMe₃)₄ with Na/Hg and of trans-OsCl₂(PMe₃)₄ with sodium in the presence of catalytic amounts of naphthalene gives the complexes RuH(η²-CH₂PMe₂)(PMe₃)₃ (III) and OsH(η²-CH₂PMe₂PMe₂), (IV) in good yields. An equilibrium with the metal(0) isomers [M(PMe₃)₄] cannot be detected by NMR spectroscopy. III and IV react with dihalomethanes CH₂X₂ (X = Cl, Br, I) and CH₃I to form mixtures of the dimethylphosphinomethanide complexes MX(η²-CH₂PMe₂)(PMe₃)₃ and the compounds MX₂(PMe₃)₄. The reactions of III and IV with the Brönsted acids HCl, HBr, CF₃CO₂H and HC₂Ph lead (with exception of M = Ru and X = C₂Ph) to the complexes cis-MX₂(PMe₃)₄. The hydrolysis of IV gives the hydrido(hydroxy) compound cis-OsH(OH)(PMe₃)₄, which has been characterized by ¹H, ³¹P NMR and mass spectroscopy. The synthesis of the complex cis-Os(CH₃)₂(PMe₃)₄ is also described; the conversion into the ethylene(hydrido)metal cation [OsH(C₂H₄)(PMe₃)₄]⁺ failed.     

Interaction of organic azides with methyl compounds of cobalt,rhodium, iridium,ruthenium and zirconium to give azido or 1,3-triazenido complexes. The crystal structures of tris-trimethylphosphineazido-dimethylcobalt(III) and bis(carbonyl)trimethylphosphineazidocobalt(I)

The interaction of azidotrimethylsilane with mer-CoMe₃(PMe₃)₃, fac-RhMe₃(PMe₃)₃, fac-IrMe₃(PMe₂Ph)₃, cis-RuMe₂(PMe₃)₄ and (η⁵-C₅H₅)₂ZrMe₂ gives tetramethylsilane and, respectively, the azido compounds MMe₂(N₃)(PMe₃)₃, M = Co, Rh, IrMe₂(N₃)(PMe₂Ph)₃, cis-Ru(N₃)₂(PMe₃)₄ and (η⁵-C₅H₅)₂ZrMe(N₃). The crystal structures of CoMe₂(N₃)(PMe₃)₃ and of the derived complex Co(N₃(CO)₂(PMe₃)₂ have been determined by X-ray diffraction.The dimethyl cobalt(III) compound has an octahedral structure with a mer arrangement of the three PMe₃ groups. The Co^III-N distance is rather long, at 2.071(4) Å. The cobalt(I) carbonyl compound has a trigonal bypyramidal structure with the two phosphines occupying the axial sites. The Co^I-N distance is 2.03(1) Å.The interaction of PhN₃ with (η⁵-C₅H₅)₂ZrR₂, R = Me, Ph, gives the 1,3-triazenido complexes (η⁵-C₅H₅)₂ZrR(RNNNPh) while mer-CoMe₃(PMe₃)₃ and p-MeC₆H₄N₃ react to give CoMe₂(MeNNNp-tol)(PMe₃)₂. In all three cases the triazenido group appears to be bidentate.