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1.
Reactivity studies of the thermally stable ruthenostannylene complex [Cp*(IXy)(H)2Ru Sn Trip] ( 1 ; IXy=1,3‐bis(2,6‐dimethylphenyl)imidazol‐2‐ylidene; Cp*=η5‐C5Me5; Trip=2,4,6‐iPr3C6H2) with a variety of organic substrates are described. Complex 1 reacts with benzoin and an α,β‐unsaturated ketone to undergo [1+4] cycloaddition reactions and afford [Cp*(IXy)(H)2RuSn(κ2‐O,O‐OCPhCPhO)Trip] ( 2 ) and [Cp*(IXy)(H)2RuSn(κ2‐O,C‐OCPhCHCHPh)Trip] ( 3 ), respectively. The reaction of 1 with ethyl diazoacetate resulted in a tin‐substituted ketene complex [Cp*(IXy)(H)2RuSn(OC2H5)(CHCO)Trip] ( 4 ), which is most likely a decomposition product from the putative ruthenium‐substituted stannene complex. The isolation of a ruthenium‐substituted stannene [Cp*(IXy)(H)2RuSn(Flu)Trip] ( 5 ) and stanna‐imine [Cp*(IXy)(H)2RuSn(κ2‐N,O‐NSO2C6H4Me)Trip] ( 6 ) complexes was achieved by treatment of 1 with 9‐diazofluorene and tosyl azide, respectively.  相似文献   

2.
Reactivity studies of the thermally stable ruthenostannylene complex [Cp*(IXy)(H)2Ru? Sn? Trip] ( 1 ; IXy=1,3‐bis(2,6‐dimethylphenyl)imidazol‐2‐ylidene; Cp*=η5‐C5Me5; Trip=2,4,6‐iPr3C6H2) with a variety of organic substrates are described. Complex 1 reacts with benzoin and an α,β‐unsaturated ketone to undergo [1+4] cycloaddition reactions and afford [Cp*(IXy)(H)2RuSn(κ2‐O,O‐OCPhCPhO)Trip] ( 2 ) and [Cp*(IXy)(H)2RuSn(κ2‐O,C‐OCPhCHCHPh)Trip] ( 3 ), respectively. The reaction of 1 with ethyl diazoacetate resulted in a tin‐substituted ketene complex [Cp*(IXy)(H)2RuSn(OC2H5)(CHCO)Trip] ( 4 ), which is most likely a decomposition product from the putative ruthenium‐substituted stannene complex. The isolation of a ruthenium‐substituted stannene [Cp*(IXy)(H)2RuSn(?Flu)Trip] ( 5 ) and stanna‐imine [Cp*(IXy)(H)2RuSn(κ2‐N,O‐NSO2C6H4Me)Trip] ( 6 ) complexes was achieved by treatment of 1 with 9‐diazofluorene and tosyl azide, respectively.  相似文献   

3.
The reaction between Ru(C≡CH)(dppe)Cp* and Co33‐CBr)(CO)9 in the presence of Pd(PPh3)4/CuI afforded dark red Co33‐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.  相似文献   

4.
A comparative study on the catalytic activity of a series of [IrCl2Cp*(NHC)] complexes in several C–O and C–N coupling processes implying hydrogen‐borrowing mechanisms has been performed. The compound [IrCl2Cp*(InBu)] (Cp*=pentamethyl cyclopentadiene; InBu=1,3‐di‐n‐butylimidazolylidene) showed to be highly effective in the cross‐coupling reactions of amines and alcohols, providing high yields in the production of unsymmetrical ethers and N‐alkylated amines. A remarkable feature is that the processes were carried out in the absence of base, phosphine, or any other external additive. A comparative study with other known catalysts, such as Shvo's catalyst, is also reported.  相似文献   

5.
The new Cp*Ru(II) (Cp*: pentamethylcyclopentadienyl) complexes Cp*(dab-R)RuCl, [Cp*(dab-R)(MeCN)Ru][PF6] (dab-R: RNCH-CHNR; R: iso-propyl, mesityl), and [Cp*(cod)(MeCN)Ru][PF6], are synthesized in high yields by reacting the corresponding α-diimine or 1,5-cyclooctadiene with [Cp*RuCl]4 and [Cp*(MeCN)3Ru][PF6], respectively. The α-diimine ligands are strongly bonded to the ruthenium centre as shown by the subsequent formation of the alkynyl derivatives Cp*(dab-R)RuCCR′ (R′ = tert-butyl or phenyl) and of the cationic derivatives [Cp*(dab-R)(L)Ru][PF6] (L = CO, PMe3). The neutral and cationic α-diimine or 1,5-cyclooctadiene ruthenium complexes are compared as catalyst precursors for the ruthenium-catalyzed allylation of diethyl-sodiomalonate and diethylamine with cinnamyl acetate or ethyl cinnamyl carbonate.  相似文献   

6.
On the Reactivity of the Ferriophosphaalkene (Z)‐[Cp*(CO)2Fe‐P=C(tBu)NMe2] towards Propiolates HC≡C‐CO2R (R=Me, Et) and Acetylene Dicarboxylates RO 2C‐C≡C‐CO2R (R=Me, Et, tBu) The reaction of equimolar amounts of (Z)‐[Cp*(CO)2Fe‐P=C(tBu)NMe2] 3 and methyl‐ and ethyl‐propiolate ( 2a, b ) or of 3 and dialkyl acetylene dicarboxylates 1a (R=Me), 1b (Et), 1c (tBu) afforded the five‐membered metallaheterocycles [Cp*(CO) =C(tBu)NMe2] ( 4a, b ) and [Cp*(CO) =C(tBu)NMe2] ( 5a—c ). The molecular structures of 4b and 5a were elucidated by single crystal X‐ray analyses. Moreover, the reactivity of 4b towards ethereal HBF4 was investigated.  相似文献   

7.
The cyclization of substituted N‐methoxy benzamides with alkynes in the presence of an easily affordable cobalt complex and NaOAc provides isoquinolone derivatives in good to excellent yields. The cyclization reaction is compatible with a range of functional group‐substituted benzamides, as well as ester‐ and alcohol‐substituted alkynes. The cobalt complex [CoIIICp*(OR)2] (R=Me or Ac) serves as an efficient catalyst for the cyclization reaction. Later, isoquinolone derivatives were converted into 1‐chloro and 1‐bromo substituted isoquinoline derivatives in excellent yields in the presence of POCl3 or PBr3.  相似文献   

8.
Monophosphine‐o‐carborane has four competitive coordination modes when it coordinates to metal centers. To explore the structural transitions driven by these competitive coordination modes, a series of monophosphine‐o‐carborane Ir,Rh complexes were synthesized and characterized. [Cp*M(Cl)2{1‐(PPh2)‐1,2‐C2B10H11}] (M=Ir ( 1 a ), Rh ( 1 b ); Cp*=η5‐C5Me5), [Cp*Ir(H){7‐(PPh2)‐7,8‐C2B9H11}] ( 2 a ), and [1‐(PPh2)‐3‐(η5‐Cp*)‐3,1,2‐MC2B9H10] (M=Ir ( 3 a ), Rh ( 3 b )) can be all prepared directly by the reaction of 1‐(PPh2)‐1,2‐C2B10H11 with dimeric complexes [(Cp*MCl2)2] (M=Ir, Rh) under different conditions. Compound 3 b was treated with AgOTf (OTf=CF3SO3?) to afford the tetranuclear metallacarborane [Ag2(thf)2(OTf)2{1‐(PPh2)‐3‐(η5‐Cp*)‐3,1,2‐RhC2B9H10}2] ( 4 b ). The arylphosphine group in 3 a and 3 b was functionalized by elemental sulfur (1 equiv) in the presence of Et3N to afford [1‐{(S)PPh2}‐3‐(η5‐Cp*)‐3,1,2‐MC2B9H10] (M=Ir ( 5 a ), Rh ( 5 b )). Additionally, the 1‐(PPh2)‐1,2‐C2B10H11 ligand was functionalized by elemental sulfur (2 equiv) and then treated with [(Cp*IrCl2)2], thus resulting in two 16‐electron complexes [Cp*Ir(7‐{(S)PPh2}‐8‐S‐7,8‐C2B9H9)] ( 6 a ) and [Cp*Ir(7‐{(S)PPh2}‐8‐S‐9‐OCH3‐7,8‐C2B9H9)] ( 7 a ). Compound 6 a further reacted with nBuPPh2, thereby leading to 18‐electron complex [Cp*Ir(nBuPPh2)(7‐{(S)PPh2}‐8‐S‐7,8‐C2B9H10)] ( 8 a ). The influences of other factors on structural transitions or the formation of targeted compounds, including reaction temperature and solvent, were also explored.  相似文献   

9.
The water‐soluble ruthenium(II) complexes [Cp′RuX(PTA)2]Y and [CpRuCl(PPh3)(mPTA)]OTf (Cp′ = Cp, Cp*, X = Cl and Y = nil; or X = MeCN and Y = PF6; PTA = 1,3,5‐triaza‐7‐phosphaadamantane; mPTA = 1‐methyl‐1,3,5‐triaza‐7‐phosphaadamantane) were used as catalyst precursors for the hydrogenation of CO2 and bicarbonate in aqueous solutions, in the absence of amines or other additives, under relatively mild conditions (100 bar H2, 30–80 °C), with moderate activities. Kinetic studies showed that the hydrogenation of HCO3? proceeds without an induction period, and that the rate strongly depends on the pH of the reaction medium. High‐pressure multinuclear NMR spectroscopy revealed that the ruthenium(II) chloride precursors are quantitatively converted into the corresponding hydrides under H2 pressure. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

10.
[{Cp*(CO)2Fe}6Sn6O8]2+, a Cationic Tin Oxo Cluster with Organometallic Substituents The reaction of [{Cp*(CO)2Fe}SnCl3] 1 (Cp* = Pentamethylcyclopentadienyl) with Ag2O in acetone leads to the formation of [{Cp*(CO)2Fe}6Sn6O8][AgCl2]2( 2 ). 2 contains the novel tin oxo cluster cation [{Cp*(CO)2Fe}6Sn6O8]2+ which consists of six {Cp*(CO)2Fe}Sn‐groups bridged by eight μ3 oxygen atoms (Sn—O = 209.2(3)‐212.5(3) pm). The resulting Sn6O8 cage exhibits a distorted rhombodocahedral structure. The [AgCl2] anion is essentially linear with a Ag—Cl bond length of 250.3(3) pm.  相似文献   

11.
Herein are described some continuing investigations into the reactions of cyano‐alkenes with diynyl‐ruthenium complexes which have resulted in the preparation and characterisation of diynyl‐ruthenium compounds Ru(C≡CC≡CR)(PP)Cp [R = Ph, PP = dppe; R = Fc, PP = dppf; R = CPh=CBr2, PP = (PPh3)2], together with the polycyanobutadienyls Ru{C≡CC[=C(CN)2]CR=CR′(CN)}(PP)Cp′ [R = Fc, (PP)Cp′ = (dppf)Cp; R = H, SiMe3, (PP)Cp′ = (dppe)Cp*] formed by [2 + 2]‐cycloaddition of the cyano‐alkenes to the outer C≡C triple bonds and subsequent ring‐opening reactions. Single‐crystal XRD molecular structure determinations of six complexes are reported.  相似文献   

12.
This review reports the contribution of the catalyst precursor RuCl(COD)C5Me5, and of the Rennes team, for the selective transformation of alkynes to generate high value chemicals with atom economy reactions. Ruthenium activation processes are discussed. Are successively presented (i) the cross-oxidative coupling of alkyne and allyl alcohol to generate γ,δ-unsaturated aldehydes, (ii) the head-to-head dimerisation of alkynes in the presence of carboxylic acids, via a mixed Fischer-Schrock type biscarbene-ruthenium complex, to give functional dienes, and that of propargyl alcohols, via cyclobutadienyl-ruthenium intermediate, to produce cyclobutene derivatives, (iii) the addition of diazoalkanes to alkynes leading to functional dienes via double carbene addition and (iv) the reaction of diazoalkanes to enynes leading to new bicyclo[3.1.0]hexane compounds. Most of the above catalytic reactions involve carbene-ruthenium catalytic species of type Cp*(Cl)Ru(biscarbene) or Cp*(Cl)RuCHR.  相似文献   

13.
The salt elimination reaction of Na[Re(CO)5] with Cp*Ru(dppm)Cl, CpRu(dppm)Cl or CpRu(CO)2Cl afforded the heterodinuclear species Cp*Ru(μ-CO)2(μ-dppm)Re(CO)3, Cp(CO)Ru(μ-dppm)Re(CO)4, or Cp(CO)2RuRe(CO)5, respectively, in moderate yields. An orthometallated species, Cp*(CO)Ru(μ-H)[μ-PhP(C6H4)CH2PPh2]Re(CO)3, was also obtained from the first reaction. All these heterodinuclear products have been characterised crystallographically. They also showed good catalytic activity for the addition of carboxylic acids to phenylacetylene to afford the anti-Markovnikov products selectively.  相似文献   

14.
A facile and efficient synthesis of N‐alkyl‐2‐(1, 2 dihydro‐1‐methylene‐4‐oxobenzo[f] isoquinoline‐3(4H)‐yl)‐2‐phenylacetamides is performed by the consecutive, two‐step procedure that consists of Ugi and Heck reactions. The Heck reaction was performed both by homogenous and a designed heterogeneous catalyst. The heterogeneous catalyst is a coordinated palladium to 1, 10‐phenanthroline attached to chitosan@Fe3O4 magnetite nanoparticles, which was shown to be more efficient than the homogenous Pd(OAc)2/PPh3 catalyst with good to excellent yields.  相似文献   

15.
Addition of Cationic Lewis Acids [M′Ln]+ (M′Ln = Fe(CO)2Cp, Fe(CO)(PPh3)Cp, Ru(PPh3)2Cp, Re(CO)5, Pt(PPh3)2, W(CO)3Cp to the Anionic Thiocarbonyl Complexes [HB(pz)3(OC)2M(CS)] (M = Mo, W; pz = 3,5‐dimethylpyrazol‐1‐yl) Adducts from Organometallic Lewis Acids [Fe(CO)2Cp]+, [Fe(CO)(PPh3)Cp]+, [Ru(PPh3)2Cp]+, [Re(CO)5]+, [ Pt(PPh3)2]+, [W(CO)3Cp]+ and the anionic thiocarbonyl complexes [HB(pz)3(OC)2M(CS)] (M = Mo, W) have been prepared. Their spectroscopic data indicate that the addition of the cations occurs at the sulphur atom to give end‐to‐end thiocarbonyl bridged complexes [HB(pz)3(OC)2MCSM′Ln].  相似文献   

16.
The reaction of [CpRuCl(PPh3)2] (Cp=cyclopentadienyl) and [CpRuCl(dppe)] (dppe=Ph2PCH2CH2PPh2) with bis‐ and tris‐phosphine ligands 1,4‐(Ph2PC≡C)2C6H4 ( 1 ) and 1,3,5‐(Ph2PC≡C)3C6H3 ( 2 ), prepared by Ni‐catalysed cross‐coupling reactions between terminal alkynes and diphenylchlorophosphine, has been investigated. Using metal‐directed self‐assembly methodologies, two linear bimetallic complexes, [{CpRuCl(PPh3)}2(μ‐dppab)] ( 3 ) and [{CpRu(dppe)}2(μ‐dppab)](PF6)2 ( 4 ), and the mononuclear complex [CpRuCl(PPh3)(η1‐dppab)] ( 6 ), which contains a “dangling arm” ligand, were prepared (dppab=1,4‐bis[(diphenylphosphino)ethynyl]benzene). Moreover, by using the triphosphine 1,3,5‐tris[(diphenylphosphino)ethynyl]benzene (tppab), the trimetallic [{CpRuCl(PPh3)}33‐tppab)] ( 5 ) species was synthesised, which is the first example of a chiral‐at‐ruthenium complex containing three different stereogenic centres. Besides these open‐chain complexes, the neutral cyclic species [{CpRuCl(μ‐dppab)}2] ( 7 ) was also obtained under different experimental conditions. The coordination chemistry of such systems towards supramolecular assemblies was tested by reaction of the bimetallic precursor 3 with additional equivalents of ligand 2 . Two rigid macrocycles based on cis coordination of dppab to [CpRu(PPh3)] were obtained, that is, the dinuclear complex [{CpRu(PPh3)(μ‐dppab)}2](PF6)2 ( 8 ) and the tetranuclear square [{CpRu(PPh3)(μ‐dppab)}4](PF6)4 ( 9 ). The solid‐state structures of 7 and 8 have been determined by X‐ray diffraction analysis and show a different arrangement of the two parallel dppab ligands. All compounds were characterised by various methods including ESIMS, electrochemistry and by X‐band ESR spectroscopy in the case of the electrogenerated paramagnetic species.  相似文献   

17.
Treatment of [Cp*(dppe)Fe? C?C‐TTFMe3] ( 1 ) with Ag[PF6] (3 equiv) in DMF provides the binuclear complex [Cp*(dppe)Fe?C?C?TTFMe2?CH? CH?TTFMe2?C?C=Fe(dppe)Cp*][PF6]2 ( 2 [PF6]2) isolated as a deep‐blue powder in 69 % yield. EPR monitoring of the reaction and comparison of the experimental and calculated EPR spectra allowed the identification of the radical salt [Cp*(dppe)Fe?C?C?TTFMe2?CH][PF6]2 ([ 1‐CH ][PF6]) an intermediate of the reaction, which results from the activation of the methyl group attached in vicinal position with respect to the alkynyl–iron on the TTF ligand by the triple oxidation of 1 leading to its deprotonation by the solvent. The dimerization of [ 1‐CH ][PF6] through carbon–carbon bond formation provides 2 [PF6]2. The cyclic voltammetry (CV) experiments show that 2 [PF6]2 is subject to two sequential well‐reversible one‐electron reductions yielding the complexes 2 [PF6] and 2 . The CV also shows that further oxidation of 2 [PF6]2 generates 2 [PF6]n (n=3–6) at the electrode. Treatment of 2 [PF6]2 with KOtBu provides 2 [PF6] and 2 as stable powders. The salts 2 [PF6] and 2 [PF6]2 were characterized by XRD. The electronic structures of 2 n+ (n=0–2) were computed. The new complexes were also characterized by NMR, IR, Mössbauer, EPR, UV/Vis and NIR spectroscopies. The data show that the three complexes 2 [PF6]n are iron(II) derivatives in the ground state. In the solid state, the dication 2 2+ is diamagnetic and has a bis(allenylidene‐iron) structure with one positive charge on each iron building block. In solution, as a result of the thermal motion of the metal–carbon backbone, the triplet excited state becomes thermally accessible and equilibrium takes place between singlet and triplet states. In 2 [PF6], the charge and the spin are both symmetrically distributed on the carbon bridge and only moderately on the iron and TTFMe2 electroactive centers.  相似文献   

18.
The metathesis reaction of Cp*(CO)3MoBr and NaW(CO)3Cp produced Cp*(CO)3Mo-W(CO)3Cp (1), featuring an unsupported Mo-W bond. Exposure of solutions of 1 to light leads to the quantitative formation of the corresponding homometallic dimers. In the solid state, the title complex exhibits an anti-arrangement of the η5-cyclopentadienyl and the η5-pentamethyl-cyclopentadienyl ligands and six terminal carbonyls. Comparison to corresponding complexes of molybdenum and tungsten reveals that the Mo-W distance is dictated by the presence of a Cp and a Cp* ligand. This is the first time that an unsupported Mo-W single bond distance is reported.  相似文献   

19.
The reactions of [η5‐Cp2ZrCl2] (Cp = η5‐C5H5) with [K(THF)n][N(PPh2)2] (n = 1.25—1.5) and K[CH(PPh2NSiMe3)2] are reported. The first reaction led to the monoamido complex [η5‐Cp2Zr(Cl)N(PPh2)2] in which the {(Ph2P)2N} ligand — via a phosphorous and the nitrogen atom — is coordinated to the zirconium atom in a chelating (η2) fashion. Reaction of the potassium methanide compound, K{CH(PPh2NSiMe3)2} with zirconocene dichloride yield the carbene‐like mono cyclopentadienyl complex [η5‐CpZr(Cl){C(PPh2NSiMe3)2}]. The complex is formed by a salt metathesis and concomitant a cyclopentadiene extrusion.  相似文献   

20.
Building upon previous studies on the synthesis of bis(sigma)borate and agostic complexes of ruthenium, the chemistry of nido‐[(Cp*Ru)2B3H9] ( 1 ) with other ligand systems was explored. In this regard, mild thermolysis of nido‐ 1 with 2‐mercaptobenzothiazole (2‐mbzt), 2‐mercaptobenzoxazole (2‐mbzo) and 2‐mercaptobenzimidazole (2‐mbzi) ligands were performed which led to the isolation of bis(sigma)borate complexes [Cp*RuBH3L] ( 2 a – c ) and β‐agostic complexes [Cp*RuBH2L2] ( 3 a – c ; 2 a , 3 a : L=C7H4NS2; 2 b , 3 b : L=C7H4NSO; 2 c , 3 c : L=C7H5N2S). Further, the chemistry of these novel complexes towards various diphosphine ligands was investigated. Room temperature treatment of 3 a with [PPh2(CH2)nPPh2] (n=1–3) yielded [Cp*Ru(PPh2(CH2)nPPh2)‐BH2(L2)] ( 4 a – c ; 4 a : n=1; 4 b : n=2; 4 c : n=3; L=C7H4NS2). Mild thermolysis of 2 a with [PPh2(CH2)nPPh2] (n=1–3) led to the isolation of [Cp*Ru(PPh2(CH2)nPPh2)(L)] (L=C7H4NS2 5 a – c ; 5 a : n=1; 5 b : n=2; 5 c : n=3). Treatment of 4 a with terminal alkynes causes a hydroboration reaction to generate vinylborane complexes [Cp*Ru(R?C?CH2)BH(L2)] ( 6 and 7 ; 6 : R=Ph; 7 : R=COOCH3; L=C7H4NS2). Complexes 6 and 7 can also be viewed as η‐alkene complexes of ruthenium that feature a dative bond to the ruthenium centre from the vinylinic double bond. In addition, DFT computations were performed to shed light on the bonding and electronic structures of the new compounds.  相似文献   

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