Reaction Of CpRu Research Articles

Cyclopentadienyl ruthenium complexes of mixed heterocyclic thiol and Bis(diphenylphosphino)ferrocene ligands

Cyclopentadienyl ruthenium complexes bearing mixed heterocyclic thiol and bis(diphenylphsphino)ferrocene (dppf) ligands are presented. The complex-salts [CpRu(dppf)(κ1S-HS-het)]PF6 {Cp = η5-C5H5; HS-het = 2-mercaptobenzothiazole (1), 2-mercaptobenzimidazole (2)} were synthesized from the reaction of CpRu(dppf)Cl with the thiol in the presence of KPF6 salt under reflux. Complexes 1 and 2 have been characterized by spectroscopic methods (1H-NMR, 31P{1H}-NMR, MS) and elemental analysis. The solid-state structures of [CpRu(dppf)(κ1SS2C7H5N)]PF6 (1) and [CpRu(dppf)(κ1S-SC7H6N2)]PF6 (2) have been determined by X-ray crystallography. The cyclic voltammetry of these two complexes are measured.

Halogen exchange by reaction of CpRu(Cl)(PPh3)2 with MeC(O)X (X = Br, I) and its mechanistic study

The treatment of CpRu(Cl)(PPh3)2 with MeC(O)X offers a very convenient procedure for the synthesis of CpRu(X)(PPh3)2. The proposed mechanism involves an intermediate produced by the concerted liberation of PPh3 by the incoming MeC(O)X and the subsequent subtraction of the X atom by the Ru atom to form a radical pair.

Reactions of the cyclopentadienyl ruthenium complexes (C5R5)Ru(cod)Cl and [(C5R5)Ru(MeCN)3]+ (R = H, Me) with phenylacetylene and acetic acid: Unexpected difference in reactivity of CpRu and Cp*Ru complexes

Reaction of CpRu(cod)Cl with phenylacetylene and AcOH gives an unusual binuclear ruthenium complex CpRu(μ-σ,η3:η3,σ-C6H3Ph3)RuCp (5, 58% yield) with a bridging acyclic flyover ligand C6H3Ph3. Under similar conditions [CpRu(MeCN)3]+ undergoes an unexpected cleavage of Cp ligand giving 4,7-diphenyl-3a,7a-dihydroindene (6, 65% yield). In sharp contrast, the pentamethylated congeners Cp*Ru(cod)Cl and [Cp*Ru(MeCN)3]+ react with phenylacetylene and AcOH in catalytic fashion giving 1,4-diphenyl-1-acetoxy-1,3-butadiene. The structures of 5 and 6 were established by X-ray diffraction. The mechanism of Cp ligand cleavage was proposed on the basis of DFT calculations.

Reactions of Ru-alkynyl Complexes with Electrophilic Boranes

The species CpRu(PPh3)2(C≡CPh) (1) reacts with HB(C6F5)2 to effect the hydroboration of the metal-bound alkyne, giving the orange species CpRu(PPh3)2CH═C(Ph)(B(C6F5)2) (2) in 95% isolated yield. Subsequent photolysis of this species results in the rearrangement of the vinyl group to give the species CpRu(PPh3)[PhC≡C(B(H)(C6F5)2)] (3) in 87% yield. The species exhibits a side-on alkyne donation to Ru as well as a bridging BH fragment. Intermediates in this conversion are discussed in relation to known species, and support for a transient zwitterionic intermediate is offered by the isolation of CpRu(PPh3)2(C═CPh(C6F4)BF(C6F5)2) (4) from the reaction of CpRu(PPh3)2(C≡CPh) with B(C6F5)3. The compounds 2–4 are crystallographically characterized.

Synthesis of cyclopentadienyl ruthenium complexes containing 5-membered N-heterocyclic thiolates

Mononuclear ruthenium–thiolate complexes of structural type CpRu(PPh 3) 2SR ( 1) [R = 2-imidazolyl ( a), 1-methylimidazolyl ( b), 5-methyl-1,3,5-thiadiazolyl ( c) and 5-methyl-4H-1,2,4-triazolyl ( d)] are accessible from the reaction of CpRu(PPh 3) 2Cl with the corresponding thiolate anions. Reaction of CpRu(PPh 3) 2Cl with the heterocyclic-thiolate anions in the presence of the bisphosphine ligands affords CpRu(P–P)SR [P–P = bis(diphenylphosphino)methane; dppm ( 2), bis(diphenylphosphino)ethane; dppe ( 3)]. If CO gas was bubbled through a THF solution of 1b, the complex CpRu(PPh 3)(CO)S(C 4N 2H 5) ( 4b) is produced. These ruthenium–heterocyclic thiolate complexes have been characterized by elemental analysis, spectroscopy (IR, 1H, 31P{ 1H} NMR and MS) and cyclic voltammetry for some samples. The solid-state structures of 3a and 3b are determined by single-crystal X-ray structure analysis.

Aqueous Organometallic Chemistry: Synthesis, Structure, and Reactivity of the Water-Soluble Metal Hydride CpRu(PTA)2H

The reaction of CpRu(PTA)2Cl (1) with KOH in methanol afforded the water-soluble hydride CpRu(PTA)2H (2) in good yield. The solid-state structures of both CpRu(PTA)2H and the previously reported CpRu(PTA)2Cl are described and exhibit classic piano stool geometries. Complex 2 is one of a very few structurally characterized CpRu(PR3)2H compounds known and the only one that is water-soluble. The ruthenium hydride is stable and soluble (S25 °C = 20 mg/mL) in deoxygenated water; however, the complex does react with chlorinated solvents to yield 1. Complex 2 undergoes H/D exchange with D2O, and the kinetics of this process were monitored by 31P NMR spectroscopy as a function of temperature. Activation parameters for the reaction of 2 with D2O were obtained: ΔH⧧ = 68 ± 2 kJ/mol; ΔS⧧ = −94 ± 7 J/mol·K. A normal kinetic isotope effect of 7.9 was calculated for the H/D exchange reaction described here. These kinetic parameters suggest an associative mechanism with little Ru−H (or Ru−D) bond cleavage at the transit...

Reaction of CpRu(PPh 3 ) 2 Cl with six-member cyclothioethers. Structures of the [CpRu(PPh 3 ) x L]Y complexes (L = pentamethylene sulfide, x = 2, Y = BF 4 − ; L = 1,3-dithiane; 1,3,5-trithiane, x = 2, Y = CF 3 SO 3 − ; L = 1,4-dithiane, x = 1, Y = BF 4 − )

The synthesis of a series of ruthenium complexes with cyclothioether ligands is reported. The compounds were characterized by X-ray diffraction techniques. The molecular structures of [CpRu(PPh3)2(pms)]BF4 (1), [CpRu(PPh3)2(1,3-dithiane)]OTfl (2), [CpRu(PPh3)2(1,3,5-trithiane)]OTfl (3), and [CpRu(PPh3)(1,4-dithiane)]BF4 (4) show chelation occurs only when the sulfur atoms are separated by at least two C atoms, creating a ligand bite size large enough to chelate. Cell parameters: 1, space group P21/c, a = 14.601(4), b = 19.102(10), c = 14.751(7) A, β = 98.28(3)○; 2, space group P21/c, a = 12.859(7), b = 15.576(3), c = 22.126(11) A, β = 102.22(4)○; 3, space group P21/c, a = 12.7320(20), b = 15.571(5), c = 22.287(4) A, β = 101.812(14)○; 4, space group Pbca, a = 11.2010(10), b = 16.321(7), c = 28.966(4) A. Compounds 2 and 3 are X-ray isomorphous. The Ru–S bond lengths range from 2.341(3), 2.365(3) A in compound 4 to 2.382(4) A in compound 2. Upon chelation (compound 4), with subsequent loss of PPh3, the Ru–P bond shortens to 2.327(3) A. This may be due to reduced steric hindrance about the Ru atom. No evidence for C–S bond lengthening is observed.

Electrochemical Oxidation of Methanol with Ru/Pd, Ru/Pt, and Ru/Au Heterobimetallic Complexes

The heterobimetallic complexes CpRu(PPh3)(μ-Cl)(μ-dppm)PdCl2 (1) [dppm = bis(diphenylphosphino)methane], CpRu(PPh3)Cl(μ-dppm)AuCl (2), and CpRu(PPh3)(μ-Cl)(μ-dppm)PtCl2 (3) were synthesized by the reaction of CpRu(PPh3)Cl(η1-dppm) (4) with Pd(COD)Cl2, AuPPh3Cl, and Pt(COD)Cl2, respectively. Compounds 1 and 2 were characterized by X-ray crystallography. Electrochemical oxidation of CH3OH in the presence of 1, 2, or 3 leads to considerable enhancement of the oxidative currents and formation of the organic products CH2(OCH3)2 and HCOOCH3. Addition of water increases both the current and the proportion of the more highly oxidized product, HCOOCH3. Current efficiencies obtained with heterobinuclear complexes 1−3 were significantly higher than those obtained using the model compound CpRuCl(η2-dppm) (5) as catalyst.

NEW RUTHENIUM(II) COMPLEXES CONTAINING ORGANODISULFIDE LIGANDS

The new complexes [CpRu(PPh3)2(RSSR)PF6 R=CH3, iso-Pr, CH2C6H5 and C6H5 have been prepared from the reaction of CpRu(PPh3)2Cl with RSSR in CH3OH in presence of NH4Cl. This result contrasts with the oxidative additions of RSSR to CpFe(dppe)1 dppe=PPh2 (CH2)2PPh2 to give [CpFe(dppe)SR]PF6 (C. Diaz et al., J. Organomet. Chem. 516, 59 (1996)). Huckel calculations on model fragments CpFe(PPh3)2 and CpRu(PPh3)2 suggest that the higher electron density of iron could explain the differences observed in reactivity. Possible biological implications are discussed.

The reactions of CpRu(PPh 3) 2SR with the electrophiles HBF 4, [MeSSMe 2]BF 4 and MeSphth where R=CMe 3, CHMe 2, 4-C 6H 4Me and phth=phthalimide

Reaction of the ruthenium thiolato complexes CpRu(PPh 3) 2SR ( 1), where R=CMe 3, CHMe 2, 4-C 6H 4Me with HBF 4 gave the corresponding thiol complex salts [CpRu(PPh 3) 2(HSR)]BF 4 ( 2) in very good yields. Treatment of the thiolato complexes with [MeSSMe 2]BF 4 gave the methyl thioether complex salt [CpRu(PPh 3) 2SMe 2]BF 4 ( 3). Reactions of 1 with MeSphth, where phth=phthalimide, gave CpRu(PPh 3) 2(phth) ( 4) and the dimers (μ-SMe)(μ-SR)[CpRu(phth)] 2 ( 5) for R=CMe 3 and CHMe 2, however, for R=4-C 6H 4Me the same reaction gave CpRu(PPh 3)(phth)(MeSS-4-C 6H 4Me) ( 6) and (μ-SMe)(μ-S-4-C 6H 4Me)[CpRu(S-4-C 6H 4Me)] 2 ( 7). The crystal structure for 7 was determined: space group P2 1/ c, a=8.805(2), b=13.668(3), c=26.026(6) Å, α=90, β=108.86(2), γ=90°, V=2964.0(12) Å 3 and Z=4.

Ruthenium heterocyclic thiolate complexes: CpRu(L)(L′)SR, [L = L′ = PPh3, 1/2 dppm, 1/2 dppe; L = PPh3, L′ = CO

The synthesis and characterization of several new ruthenium complexes containing heterocyclic thiolate ligands are described. CpRu(PPh3)2Cl reacts with thiolate anions to give CpRu(PPh3)2SR, (1) [R = 2-mercaptobenzimidazolyl (a), 2-mercaptobenzothiazolyl (b), and 2-mercaptobenzoxazolyl (c)] in good yields. The CpRu(PPh3)-(CO)SR (2) complexes are obtained by treating (1) with CO gas in THF at room temperature. The one-pot reaction of CpRu(PPh3)2Cl, thiolate anions with chelate bisphosphine ligands (P–P), gave CpRu(P–P)SR where P–P = Ph2PCH2PPh2 (dppm) (3); Ph2PCH2CH2PPh2 (dppe) (4).

Optically active transition metal complexes. Part 115 . Synthesis, crystal structure and properties of chiral ( η5-C 5H 5)Ru complexes with pyrrolecarbaldiminato and salicylaldiminato ligands

The chiral complexes CpRu(LL*)PPh 3, Cp= η 5-C 5H 5, LL*-1=anion of 2- N-[( S)-l-phenylethyl]pyrrolecarbaldimine ( 1a/ 1b), LL*-2=anion of 2- N-[( R)-hydroxybut-2-yl)]pyrrolecarbaldimine ( 2a/ 2b) and LL*-3=anion of N-[( S)-1-phenylethyl]salicylaldimine ( 3a/ 3b), can be prepared by reaction of CpRu(PPh 3) 2Cl and the corresponding ligand HLL* in boiling toluene. An X-ray structure analysis of diastereomerically pure 1a shows S Ru configuration. The phenyl substituent of the ligand adopts a T-shape arrangement with respect to the Cp ring. The PPh 3 ligand is in a right handed propeller conformation. The activation parameters of the epimerization 1a⇌ 1b were determined to be Δ H ≠=(133±33) kJ mol −1 and Δ S ≠=(77±26) J K −1 mol −1. The equilibrium ratios are 1a: 1b=86:14, 2a: 2b=1:1 and 3a: 3b=88:12, the attractive interaction between the Cp ring and the phenyl substituent of the chiral center in the chelating ligand LL* favoring one diastereomer of the complexes 1a/ 1b and 3a/ 3b.

Molecular structure of [CpRu(PPh3)2(tht)]BF4, tht=tetrahydrothiophene

The title compound [CpRu(PPh3)2(tht)]BF4,1, tht=tetrahydrothiophene, is obtained by the reaction of CpRu(PPh3)2Cl, tht and AgBF4 in CH2Cl2 solution. Yellow crystals of [CpRu(PPh3)2(tht)]BF4 were grown by the slow diffusion of pentane into a CH2Cl2 solution of1 and have been studied by X-ray crystallography: space group is P21/n,a=9.507(2),b=18.336(3),c=22.372(6) A, β=94.28(2)°,V=3889(1) A3,Z=4. The tht ligand binds to the Ru atom through the sulfur atom at a distance of 2.395(2) A. The tht ring is in the puckered configuration.

The reaction of CpRu(PPh 3) 2+ with trimethylenesulfide. Synthesis and molecular and crystal structure of [CpRu(PPh 3) 2(SC 3H 6)]CF 3SO 3

The isolation and characterization of the trimethylenesulfide-coordinated complex, [CpRu(PPh 3) 2(SC 3H 6)]CF 3SO 3, is reported. The structure of [CpRu(PPh 3) 2(SC 3H 6)]CF 3SO 3 was determined by X-ray diffraction techniques: monoclinic space group I2/a, a=23.864(10), b=14.233(3), c=24.385(7) Å, β=97.10(3)°, Z=8, R=0.046, R w=0.065. The Ru is attached to two triphenylphosphine ligands, a cyclopentadienyl and the trimethylenesulfide. The Ru-S distance is 2.3459(20) Å.

The reaction of CpRu(PPh 3) 2+ with organic thiols. Synthesis and characterization of [CpRu(PPh 3) 2(RSH)]BF 4 (R=benzyl, phenethyl) and the molecular and crystal structure of [CpRu(PPh 3) 2(C 6H 5CH 2CH 2SH)]BF 4·CH 2Cl 2

The isolation and characterization of two mercaptan complexes of the general formula [CpRu(PPh 3) 2(RSH)]BF 4, where R=benzyl and phenethyl, were undertaken to model the substrate/catalyst interaction of the hydrode-sulfurization (HDS) process. The IR data show a shift in the SH stretching frequency upon coordination. The structure of the [CpRu(PPh 3) 2(C 6H 5CH 2CH 2SH)]BF 4 complex was determined by X-ray diffraction techniques: monoclinic space group P2 1/ n, a=15.317(4), b=13.924(9), c=21.815(7) Å, β=95.20(2)°, Z=4, R=0.057, R w=0.073. The Ru is attached to two triphenylphosphine ligands, a cyclopentadienyl and the phenethylmercaptan. The Ru-S distance is 2.369(2) Å and the S-H distance is 1.18 Å.

Haloalkyl complexes of the transition metals : II. Some new chloromethyl and methoxymethyl complexes of manganese, rhenium and ruthenium

The reactions of Na[Mn(CO) 5] or Na[Mn(CO) 4(PPh 3)] with CH 2ClI yield the new chloromethyl complexes Mn(CO) 5CH 2Cl and Mn(CO) 4(PPh 3)CH 2Cl. Reaction of Na[Re(CO) 5] or Na[CpRu(CO) 2] with ClCH 2OMe yields Re(CO) 5CH 2Cl and CpRu(CO) 2CH 2Cl respectively, in addition to the corresponding methoxymethyl complexes (Cp = η 5-C 5H 5). Reaction of CpRu(CO) 2CH 2OMe with HCl yields the corresponding chloromethyl complex.