Oxidative cleavage of the FeFe bond in [C5Me5Fe(CO)2]2 using ferrocinium ion: A facile route to the synthetically useful complexes [C5Me5Fe(CO)2(solvent)]+

Complexes of the type {Fp′(solvent)}⁺ PF₆^?, 3a–3d, (Fp′ = (η -C₅Me₅)Fe(CO)₂, solvent = THF, CH₃COCH₃, CH₃CN, or pyridine) are conveniently prepared by the reaction between Fp′₂ and Cp₂Fe⁺ PF₆ (Cp = η⁵-C₅H₅) in the solvent under ambient conditions. The complexes {Fp′L}⁺ PF₆^?, 3e–3g, (L = CO, PPh₃, P(OPh)₃) are readily prepared from {Fp′THF}⁺. Fp′H is formed by treatment of 3a with NaBH₄. Fp′SC(S)NMe₂ can be prepared from 3a or 3e and NaSC(S)NMe₂.     

Potential inhibitors of DNA topoisomerase II: ruthenium(II) poly-pyridyl and pyridyl-azine complexes

In search of new DNA probes a series of new mono and binuclear cationic complexes [RuH(CO)(PPh₃)₂(L)]⁺ and [RuH(CO)(PPh₃)₂(-μ-L)RuH(CO)(PPh₃)₂]²⁺ [L=pyridine-2-carbaldehyde azine (paa), p-phenylene-bis(picoline)aldimine (pbp) and p-biphenylene-bis(picoline)aldimine (bbp)] have been synthesized. The reaction products were characterized by microanalyses, spectral (IR, UV-Vis, NMR and ESMS and FAB-MS) and electrochemical studies. Structure of the representative mononuclear complex [RuH(CO)(PPh₃)₂(paa)]BF₄ was crystallographically determined. The crystal packing in the complex [RuH(CO)(PPh₃)₂(paa)]BF₄ is stabilized by intermolecular π-π stacking resulting into a spiral network. Topoisomerase II inhibitory activity of the complexes and a few other related complexes [RuH(CO)(PPh₃)₂(L)]⁺ {L=2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz) and 2,3-bis(2-pyridyl)-pyrazine (bppz)} have been examined against filarial parasite Setaria cervi. Absorption titration experiments provided good support for DNA interaction and binding constants have also been calculated which were found in the range 1.2 × 10³-4.01 × 10⁴ M⁻¹.     

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.     

Mixed ligand complexes of platinum(0) containing diphosphines

The reaction of PtCl₂L (L = diphosphine) with the appropriate diphosphine L′ in ethanol followed by reduction with aqueous sodium borohydride leads to either disproportionation to give mixtures of the bis(diphosphine) complexes PtL₂ and PtL′₂ or to the formation of the mixed ligand complex PtLL′ depending on the diphosphines. Mixed ligand complexes are obtained when L=Ph₂P(CH₂)₂PPh₂, L′ = Ph₂P(CH₂PPh₂cis-Ph₂PCH CHPPh₂, Ph₂P(CH₂)₂AsPh₂, Ph₂- P(CH₂)₄PPh₂, o-Ph₂PC₆H₄PPh₂; and L=(C₆H₁₁)₂P(CH₂₂P(C₆H₁₁)₂, L′= Ph₂P(CH₂)PPh₂, Ph₂P(CH₂)₂PPh₂cis-Ph₂PCHCHPPh₂, (2S,3S)-Ph₂PCH- (CH₃)CH(CH₃)PPh₂, (R)-Ph₂PCH(CH₃)CH₂PPh₂. When L=Ph₂P(CH₂)₄PPh₂ L′= Ph₂P(CH₂₃PPh₂ or cis-Ph₂PCHCHRPh₂ the mixed ligand complexes are obtained but extensive disproportionation also occurs.     

Schwefel(IV)-Verbindungen als Liganden: XIV. [(C5H5)Ru(dppm)(CH2=SO2)]+, ein starkes metallorganisches electrophil

Diazomethane converts [cpRu(dppm)(SO₂)]PF₆ into [cpRu(dppm)(CH₂=SO₂)]PF₆, the first example of a complex containing a side-on coordinated sulfene. This compound is a strong organometallic electrophile as shown by rapid addition reactions with anionic (Cl⁻, Br⁻, CN⁻, SCN⁻) and neutral (PMe₃, PPh₃, NMe₂Ph, MeOH, EtOH) nucleophiles.     

Novel structures of cyclometallated complexes of palladium(II) derived from terdentate ligands. Crystal and molecular structure of [Pd{C6H4C(H)=NCH2CH2CH2NMe2}(X)] (X=Cl, Br, I)

Treatment of N-(2-chlorobenzylidene)-N,N-dimethyl-1,3-propanediamine (1) and N-(2-bromo-3,4-(MeO)₂-benzylidene)-N,N-dimethyl-1,3-propanediamine (20) with tris(dibenzylideneacetone)dipalladium(0) in toluene gave the mononuclear cyclometallated complexes [Pd{C₆H₄C(H)=NCH₂CH₂CH₂NMe₂}(Cl)] (2) and [Pd{3,4-(MeO)₂C₆H₂C(H)=NCH₂CH₂CH₂NMe₂}(Br)] (21), respectively, via oxidative addition reaction with the ligand as a C,N,N terdentate ligand. Reaction of 2 with sodium bromide or iodide in an acetone–water mixture gave the cyclometallated analogues of 2, [Pd{C₆H₄C(H)=NCH₂CH₂CH₂NMe₂}(Br)] (3) and [Pd{C₆H₄C(H)=NCH₂CH₂CH₂NMe₂}(I)] (4), by halogen exchange. The X-ray crystal structures of 2, 3 and 4 were determined and discussed. Treatment of 2, 3, 4 and 21 with tertiary monophosphines in acetone gave the mononuclear cyclometallated complexes [Pd{C₆H₄C(H)=NCH₂CH₂CH₂NMe₂}(L)(X)] (6: L=PPh₃, X=Cl; 7: L=PPh₃, X=Br; 8: L=PPh₃, X=I; 9: L=PMePh₂, X=Cl; 10: L=PMe₂Ph, X=Cl) and [Pd{3,4-(MeO)₂C₆H₂C(H)=NCH₂CH₂CH₂NMe₂}(L)(Br)] (22: L=PPh₃; 23: L=PMePh₂; 24: L=PMe₂Ph). A fluxional behaviour due to an uncoordinated CH₂CH₂CH₂NMe₂ could be determined by variable temperature NMR spectroscopy. Treatment of 2, 3 and 4 with silver trifluoromethanesulfonate followed by reaction with triphenylphosphine gave the mononuclear complex [Pd{C₆H₄C(H)=NCH₂CH₂CH₂NMe₂}(PPh₃)][F₃CSO₃] (11) where the Pd–NMe₂ bond was retained. Reaction of 2, 3 and 4 with ditertiary diphosphines in a cyclometallated complex–diphosphine 2:1 molar ratio gave the binuclear complexes [{Pd[C₆H₄C(H)=NCH₂CH₂CH₂NMe₂](X)}₂(μ-L–L)][L–L=PPh₂(CH₂)₄PPh₂(dppb) (13, X=Cl; 14, X=Br; 15, X=I; L–L=PPh₂(CH₂)₅PPh₂(dpppe): 16, X=Cl; 17, X=Br; 18, X=I) with palladium–NMe₂ bond cleavage. Treatment of 2, 3 and 4 with ditertiary diphosphines, in a cyclometallated complex–diphosphine 2:1, molar ratio and AgSO₃CF₃ gave the binuclear cyclometallated complexes [{Pd[C₆H₄C(H)=NCH₂CH₂CH₂NMe₂]}₂(μ-L–L)][F₃CSO₃]₂ (11: L–L=PPh₂(CH₂)₄PPh₂(dppb), X=Cl; 12: L–L=PPh₂(CH₂)₅PPh₂ (dpppe), X=Cl). Reaction of 2 with the ditertiary diphosphine cis-dppe in a cyclometallated complex–diphosphine 1:1 molar ratio followed by treatment with sodium perchlorate gave the mononuclear cyclometallated complex [Pd{C₆H₄C(H)=NCH₂CH₂CH₂NMe₂}(cis-PPh₂CH=CHPPh₂–P,P)][ClO₄] (19).     

Hydride-phosphoniodithiocarboxylate/ phosphonium-betaine isomerism in Cy3PCS2 complexes of ruthenium

Reaction of Cy₃PCS₂ (Cy = cyclohexyl) with the hydrido complexes [RuClH(CA)(PPh₃)₃] (A  O, S), [RuH(CO)(NCMe)₂(PPh₃)₂]⁺, and [RuH(OClO₃)(CO)(CN^tBu)(PPh₃)₂] leads to the complex cations [RuH(CA)(PPh₃)₂(η²-S₂CPCy₃)]⁺, [Ru(η²-S₂CHPCy₃)(CO) (PPh₃)₂]⁺, [RuH(η¹-S₂CPCy₃)(CO)(CN^tBu)(PPh₃)₂]⁺. The σ-vinyl complex [Ru(CHCHC₆H₄Me-4)Cl(CO)(PPh₃)₂] reacts with Cy₃PCS₂ to give the cationic complex [Ru(CHCHC₆H₄Me-4) (CO)(PPh₃)₂(η²-S₂CPCy₃)]⁺, but this complex is not formed by hydroruthenation of HCCC₆H₄Me-4 by [RuH(CO)(PPh₃)₂(η²-S₂CPCy₃)]⁺. The inter-relationships between the above complexes are discussed.     

Mononuclear hydridocarbonyl ruthenium complexes incorporating N2O2 bis-chelating ligands

The reactions of [RuH(CO)Cl(PPh₃)₃] with N,N^′-bis(salicylidine)-hydrazine (H₂bsh) and N,N^′-bis(salicylidine)-p-phenylene diammine (H₂bsp) in presence of KOH in methanol led in the formation of neutral mononuclear complexes with the formulations [RuH(CO)(PPh₃)₂(L)] (LHbsh or Hbsp). These present the first examples where the ligands H₂bsh or H₂bsp provide only two of its available donor sites for interaction with the metal centre. The complexes have been characterized by elemental analyses, FAB-MS, IR, ¹H, ¹³C, ³¹P NMR and electronic spectral studies. Molecular structure of the representative complex [RuH(CO)(PPh₃)₂(Hbsh)] have been determined by single crystal X-ray analysis.     

Molecular and spectroscopic properties of hydridecarbonyl ruthenium complexes with pyrazine carboxylic acid ligands

The hydride carbonyl ruthenium(II) [RuH(CO)(pyzCOO)(PPh₃)₂] (1), [RuH(CO)(pyz-2,3-COO[CH₃])(PPh₃)₂]·H₂O (2) and dinuclear Ru(II)/Ru(III) [RuH(CO)(PPh₃)(pyz-2,3-COO)Ru(CO)Cl₂(PPh₃)₂] (3) complexes were synthesized and characterized by IR, ¹H, ³¹P NMR, UV-Vis spectroscopy and X-ray crystallography. The experimental studies were complemented by quantum chemical calculations, which were used to identify the nature of the interactions between the ligands and the central ion, and the orbital composition in the frontier electronic structure. Based on a molecular orbital scheme, the calculated results allowed the interpretation of the UV-Vis spectra obtained at an experimental level. The luminescence property of the complex 2 was determined. The ac magnetic susceptibility measurements showed a residual magnetism evidenced by the small values of the molar susceptibility, not exceeding 0.5 emu/mol at 2 K, a lack of a Curie-Weiss region and weak magnetic interactions below 20 K.     

Water–gas shift reaction catalyzed by mononuclear ruthenium complexes containing bipyridine and phenanthroline derivatives

Ruthenium complexes of the type [RuL(CO)₂Cl₂], [RuL₂Cl₂], [RuL₂(CO)(H₂O)](PF₆)₂, [RuL₂Cl]₂(PF₆)₂, [RuL₂(CO)Cl](PF₆), and [RuL₂(CO₃)]·3H₂O (where L is a bipyridine or phenanthroline derivative) dissolved in aqueous 2‐ethoxyethanol, and in a basic medium of KOH, triethylamine, or trimethylamine, catalyze the water‐gas shift reaction under mild conditions (P_CO = 0.9 atm at 100 °C). Copyright © 2002 John Wiley & Sons, Ltd.     

Alcohol oxidation reactions catalyzed by ruthenium–carbonyl complexes of thioarylazoimidazoles

Alcohols are oxidized by N‐methylmorpholine‐N‐oxide (NMO), Bu^tOOH and H₂O₂ to the corresponding aldehydes or ketones in the presence of catalyst, [RuH(CO)(PPh₃)₂(SRaaiNR′)]PF₆ ( 2 ) and [RuCl(CO)(PPh₃)(S_κRaaiNR′)]PF₆ ( 3 ) (SRaaiNR′ ( 1 ) = 1‐alkyl‐2‐{(o‐thioalkyl)phenylazo}imidazole, a bidentate N(imidazolyl) (N), N(azo) (N′) chelator and S_κRaaiNR′ is a tridentate N(imidazolyl) (N), N(azo) (N′), S_κ‐R is tridentate chelator; R and R′ are Me and Et). The single‐crystal X‐ray structures of [RuH(CO)(PPh₃)₂(SMeaaiNMe)]PF₆ ( 2a ) (SMeaaiNMe = 1‐methyl‐2‐{(o‐thioethyl)phenylazo}imidazole) and [RuH(CO)(PPh₃)₂(SEtaaiNEt)]PF₆ ( 2b ) (SEtaaiNEt = 1‐ethyl‐2‐{(o‐thioethyl)phenylazo}imidazole) show bidentate N,N′ chelation, while in [RuCl(CO)(PPh₃)(S_κEtaaiNEt)]PF₆ ( 3b ) the ligand S_κEtaaiNEt serves as tridentate N,N′,S chelator. The cyclic voltammogram shows Ru^III/Ru^II (~1.1 V) and Ru^IV/Ru^III (~1.7 V) couples of the complexes 2 while Ru^III/Ru^II (1.26 V) couple is observed only in 3 along with azo reductions in the potential window +2.0 to ?2.0 V. DFT computation has been used to explain the spectra and redox properties of the complexes. In the oxidation reaction NMO acts as best oxidant and [RuCl(CO)(PPh₃)(S_κRaaiNR′)](PF₆) ( 3 ) is the best catalyst. The formation of high‐valent Ru^IV=O species as a catalytic intermediate is proposed for the oxidation process. Copyright © 2014 John Wiley & Sons, Ltd.     

Alkyl- und Arylkomplexe des Iridiums und Rhodiums. XIX. Reaktion von Carbonsäuren mit ausgewählten Organoverbindungen von Ir(I) und Rh(I): Bildung von Arylhydrido-, Carboxylatohydrido- und Carboxylato-Derivaten

Alkyl and Aryl Complexes of Iridium and Rhodium. XIX. Reaction of Carboxylic Acids with Selected Organo Compounds of Ir(I) and Rh(I): Formation of Arylhydrido, Carboxylatohydrido, and Carboxylato Derivatives cis-Arylhydridoiridium(III) complexes IrH(Ar)(O₂CR)(CO)(PPh₃)₂ (R = Me: Ar = C₆H₅, 4-MeC₆H₄; R = Et: Ar = 4-MeC₆H₄, 2,4-Me₂C₆H₃) could be prepared by oxidative addition of carboxylic acids to aryliridium(I) compounds Ir(Ar)(CO)(PPh₃)₂. Reaction of aliphatic carboxylic acids with alkyliridium(I) derivatives Ir(Alk)(CO)(PPh₃)₂ and Ir(Alk)[PhP(CH₂CH₂CH₂PPh₂)₂] (Alk = CH₂CMe₃, CH₂SiMe₃) lead to dicarboxylatoiridium(III) hydrides IrH(O₂CR)₂(CO)(PPh₃)₂ (R = Me, Et, i-Pr) and IrH(O₂CR)₂[PhP(CH₂CH₂CH₂PPh₂)₂] (R = Me, Et). Ir(4-MeC₆H₄CO₂)(CO)(PPh₃)₂ was obtained from Ir(CH₂SiMe₃)(CO)(PPh₃)₂ and 4-MeC₆H₄CO₂H. Interaction of organorhodium complexes Rh(R′)(CO)(PPh₃)₂ (R′ = CH₂SiMe₃, 4-MeC₆H₄) and Rh(R′)[PhP(CH₂CH₂CH₂PPh₂)₂] (R′ = CH₂CMe₃, 4-MeC₆H₄) with aliphatic and aromatic carboxylic acids yielded carboxylatorhodium(I) compounds Rh(O₂CR)(CO)(PPh₃)₂ (R = Me, t-Bu, 4-MeC₆H₄) and Rh(O₂CR)[PhP(CH₂CH₂CH₂PPh₂)₂] (R = Me, 4-MeC₆H₄).     

Insertions of phenylacetylene with chelated bis(triphenylphosphine) - ruthenium(II)hydridocarbonyl complexes

Summary Phenylacetylene reacts stoichiometrically or in excess with the Ru—H bond of RuH(CO)(PPh₃)₂(L) (LH = 2-hydroxypyridine, 2-hydroxy-6-methylpyridine, acetylacetone, benzoylacetone, 2-hydroxyacetophenone, 2-hydroxypropiophenone, 2-hydroxybenzophenone and 4-methoxy-2-hydroxybenzophenone) in boiling benzene to give -vinylic or -vinylalkynyl complexes of the type Ru(CO)-(PPh₃)₂(L)(CH CHPh) and Ru(CO)(PPh₃)₂(L){C-(C CPh) CHPh} in good yield. The vinylic complex can also be obtained by reacting the sodio derivative of the chelating ligand with the 16e^– unsaturated complex, [Ru(CO)Cl(CH CHPh)(PPh₃)₂], in CH₂Cl₂/MeOH mixture at ambient temperature. These complexes have been characterized by elemental analyses, and i.r., ¹H, ¹³C and ³¹P n.m.r. spectroscopy.N.C.L Communication No. 5404.     

Synthesis,characterization and catalytic studies of ruthenium(II) chalconate complexes

Stable ruthenium(II) carbonyl complexes of the type [RuCl(CO)(EPh₃)(B)(L)] (E = P or As; B = PPh₃, AsPh₃ or Py; L = 2′‐hydroxychalcones) were synthesized from the reaction of [RuHCl(CO)(EPh₃)₂(B)] (E = P or As; B = PPh₃, AsPh₃ or Py) with 2′‐hydroxychalcones in benzene under reflux. The new complexes were characterized by analytical and spectroscopic (IR, electronic ¹H, ³¹P and ¹³C NMR) data. They were assigned an octahedral structure. The complexes exhibited catalytic activity for the oxidation of primary and secondary alcohols into their corresponding aldehydes and ketones in the presence of N‐methylmorpholine‐N‐oxide (NMO) as co‐oxidant and were also found to be efficient transfer hydrogenation catalysts. Copyright © 2008 John Wiley & Sons, Ltd.     

X-ray structure of fac-[RuH(1,5-cod)(NH2NMe2)3][PF6]: Stabilization of coordinated substituted hydrazines by hydrogen bonding

The structure of [RuH(cod)(NH₂NMe₂)₃][PF₆] has been solved by X-ray diffraction methods and shows the cation to contain a facial arrangement of N,N-dimethylhydrazine ligands, coordinated via the NH₂ nitrogen atoms, and held together by hydrogen bonds.     

Chemistry of (η5-C5H5)Ru(Ph2PCH2CH2PPh2)Cl: preparation of cationic ruthenium olefin complexes

The cationic ruthenium complexes [(η⁵-C₅H₅)Ru(Ph₂PCH₂CH₂PPh₂)L]PF₆ (L=olefin, CO, pyridine or acetonitrile) have been prepared by treatment of (η⁵-C₅H₅)Ru(Ph₂PCH₂CH₂PPh₂)Cl with L and NH₄PF₆ in methanol of 20°C.     

Group V complexes of the tricarbonyl(η-cycloheptatrienylium)molybdenum cation and their reduction to monosubstituted derivatives of tricarbonyl(1-6-η-cycloheptatriene)molybdenum

Reaction of [(η-C₇H₇)Mo(CO)₃][PF₆] with certain Group V donor ligands afforded monosubstituted complexes [(η-C₇H₇)Mo(CO)₂L][PF₆] (L = P(OPh)₃, PPh₃, PPh₂Me, PPhMe₂, AsPh₃, SbPh₃). These were reduced by NaBH₄ to the corresponding cycloheptatriene complexes (1-6-η-C₇H₈)Mo(CO)₂L. In addition, the preparation of alkylcycloheptatriene complexes (1-6-η-C₇H₇R)Mo(CO)₂L (R = Me, L = P(OPh)₃, PPh₃, PPh₂Me; R = t-Bu, L = PPh₃) is described. Spectroscopic properties, including ¹³C NMR, are reported.     

P-C Bond Cleavage in Platinum Complexes Containing bis (Diphenylphosphino) Methane Promoted with a Phase-Transfer Catalyst

With a phase-transfer catalyst, Pt-dppm (dppm = Ph₂PCH₂PPh₂) complexes undergo basic hydrolysis, in which a dppm ligand is hydrolyzed to produce PPh₂Me and PPh₂OH (or PPh₂O). The ease of this hydrolysis reaction depends partly on the molecular charges of the metal complexes. Hydrolysis of neutral [Pt(dppm)(L-L)] (L-L = S₂CO², S₂P(O)(OEt)^2? and mnt = S₂C₂(CN)₂^2?) is slower than that of monocationic [Pt(dppm)(L′-L′)]Cl (L′-V = S₂CNEt₂-, (CH₂)₂S(O)Me and acetylacetonate) compounds. Among the neutral compounds, hydrolysis of [Pt(dppm)(mnt)] is more rapid than that of the other two. These results are rationalized according to the ease with which partial positive charges are induced on the dppm phosphorus atoms. The steric effect due to ligands trans to dppm also influences the rate of hydrolysis of Pt-dppm compounds. When trans ligands are Ph₂P(CH)₂PPh₂, Ph₂P(CH₂)₃PPh₂ and (Ph₂PO₂)H, no hydrolysis of dppm occurs. Hydrolysis of Pt-dppm compounds depends further on the concentrations of both the phase-transfer catalyst and OH^? ions. All these results are consistent with nucleophilic attack of OH^? on dppm phosphorus atoms to release strain in the Pt-dppm ring.     

Synthesis,spectroscopic and structural characterizations of two new complexes of ruthenium with 2-(hydroxymethyl)benzimidazole and 1,10-phenanthroline ligands

The complexes [RuCl(CO)(PPh₃)₂(HBIm)] and [RuH(CO)(PPh₃)₂(1,10-phen)]Cl·H₂O·(CH₃)₂O have been prepared and studied by IR and UV–Vis spectroscopy, and X-ray crystallography. The complexes were prepared in the reactions of [RuHCl(CO)(PPh₃)₃] with 2-(hydroxymethyl)benzimidazole or 1,10-phenanthroline two hydrate in acetone. The electronic spectra of the obtained compounds have been calculated using the TDDFT method. The luminescence properties of these complexes were examined.     

THE REACTIONS OF [MoCl(GeCl3)(CO)3(NCMe)2] WITH NEUTRAL BI- AND TERDENTATE DONOR LIGANDS

Abstract

The reaction of [MoCl(GeCl₃)(CO)₃(NCMe)₂] with an equimolar quantity of L?L {L?L = 2,2′-bipy, 1,10-phen, Ph₂P(CH₂)_nPPh₂ (n = 1 or 2)} in CH₂Cl₂ at room temperature gave either [MoCl(GeCl₃)(CO)₃(L?L)] (L?L = 2,2′-bipy or 1,10-phen) (1 and 2) or [MoCl(GeCl₃)(CO)₂ (NCMe)(L?L)]{L?L = Ph₂P(CH₂)_nPPh₂ (n = 1 or 2) (3 or 4), respectively. Equimolar quantities of [MoCl(GeCl₃)(CO)₂(NCMe){Ph₂P(CH₂)PPh₂}] (3) and L?L {L?L = 2,2′-bipy or Ph₂P(CH)₂PPh₂} react in CH₂Cl₂ at room temperature to afford the cationic complexes [Mo(GeCl₃)(CO)₂{Ph₂P(CH₂) PPh₂}(L?L)]Cl (5 and 6) in good yield. The cationic nature of 6 was established by chloride exchange by reacting Na[BPh₄] with 6 in acetonitrile to give the tetraphenylborate complex [Mo(GeCl₃)(CO)₂{Ph₂P(CH₂)PPh₂}₂][BPh₄] (7). Reaction of equimolar quantities of [MoCl(GeCl₃) (CO)₃(NCMe)₂] and PhP(CH₂CH₂PPh₂)₂ in CH₂Cl₂ at room temperature afforded the dicarbonyl complex [MoCl(GeCl₃)(CO)₂{PhP(CH₂CH₂PPh₂)₂}] (8) in good yield.