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1.
The carbene ruthenium complex [1,3-bis(2,6-dimethylphenyl)-4,5-dihydroimidazol-2-ylidene](C5H5N)2(Cl)2RuCHPh (8) was prepared by the reaction of [1,3-bis (2,6-dimethylphenyl)-4,5-dihydroimidazol-2-ylidene](PPh3)(Cl)2RuCHPh (7) with pyridine and used as a highly effective catalyst for the cross-metathesis of acrylonitrile with various functionalized olefins.  相似文献   

2.
Bis(NHC) ruthenium benzylidene complex (H2IMe)2(Cl)2RuCHPh (9) [H2IMe = 1,3-bis(2,6- dimethylphenyl)-4,5-dihydroimidazol-2-ylidene] was synthesized facilely by one-step reaction of (PPh3)2(Cl)2RuCHPh (7) with N-heterocyclic carbene (NHC) H2IMe (6). Complex 9 proved to exhibit remarkable catalytic activity for ring-closing metathesis (RCM) reaction at increased temperature.  相似文献   

3.
4.
Ruthenium benzylidene complex (H2IMes)(2-CH3-C5H4N)(Cl)2RuCHPh [H2IMes = 1,3-bis(2,6-dimethylphenyl)-4,5-dihydroimidazol-2-ylidene] (4), which introduced ortho substituted pyridine as dissociating ligand to weaken Ru-N bond and accelerate initiation through steric hindrance, was prepared by the reaction of (H2IMes)(PPh3)(Cl)2RuCHPh (1) with 2-methylpyridine and proved to exhibit enhanced catalytic activity for cyano-contained olefin metathesis.  相似文献   

5.
The synthesis of the new ruthenium(II) allenylidene complex [ClRu(dppe)2CCC11H6N2][OTf] (4) (dppe = 1,2-bis(diphenylphosphino)ethane) terminated with a 4,5-diazafluorene ligand is reported. Further coordination of that metal allenylidene to ruthenium and rhenium moieties leads to the bimetallic adducts [ClRu(dppe)2CCC11H6N2{Ru(bpy)2}][B(C6F5)4]3 (5a), [ClRu(dppe)2CCC11H6N2{Ru(tBu-bpy)2}][PF6]3 (5b) and [ClRu(dppe)2CCC11H6N2{Re(CO)3Cl}][OTf] (6). Their optical and electrochemical properties show that the allenylidene moiety is an attractive molecular clip for the access to larger original redox-active homo/heteronuclear multi-component supramolecular assemblies. The X-ray crystal structure of the allenylidene metal building block is also described.  相似文献   

6.
The reaction of (Ph3P)3RuCl2 with 1,1-diphenyl-2-propyn-1-ol was investigated in various solvents. The reaction in thf under reflux is reported to produce the (PPh3)2Cl2Ru(3-phenylindenylidene) complex (3) which has undergone rearrangement of the allenylidene C3-spine. We have improved the reliability of the reported synthesis by adding acetyl chloride which converts the formed water of the reaction and thus increases the acidity of the reaction solution. Without the additive, we observed the exclusive formation of an intermediate of the transformation and identified it as dinuclear (PPh3)2ClRu(μ-Cl)3(PPh3)2RuCCCPh2 complex (5). The reaction of (Ph3P)3−4RuCl2 with 1,1-diphenyl-2-propyn-1-ol in CH2Cl2 or C2H4Cl2 under reflux in the presence of excess conc. aqueous HCl afforded the new, neutral (PPh3)2Cl3RuC-CHCPh2 carbyne complex (7), an HCl adduct of previously elusive (PPh3)2Cl2RuCCCPh2 complex 6 in high yields. In contrast to the formation of complex 3, the reaction in a non-coordinating solvent did not afford the rearrangement of the allenylidene C3-spine. Complex 7 was converted into complex 3 in thf under reflux under loss of a molecule HCl. Complex 7 was converted with triethylamine under loss of HCl to complex 6. Pentacoordinate complex 6 was crystallized in the presence of O-donor ligands (EtOH, MeOH and H2O) to give hexacoordinate (PPh3)2Cl2(ROH)RuCCCPh2 (R = H, CH3, C2H5) complexes (9)-(11) with the O-donor coordinating in trans-position to the allenylidene moiety. The reaction of complex 7 with 2 equiv. of 4-(N,N-dimethylamino)pyridine (DMAP) gave hexacoordinate (PPh3)2Cl2(DMAP)RuCCCPh2complex (12) with one molecule DMAP also coordinating in trans-position to the allenylidene group. Methanol and acetic acid in the absence of strong bases afforded the Fischer-carbene complexes (PPh3)2Cl2RuC(OCH3)-CHCPh2 (14) and (PPh3)2Cl2RuC(OAc)-CHCPh2 (15) where the nucleophile added to the α-carbon atom. The structures of complexes 5, 7, 9-11, 14, and 15 were solved via X-ray crystallography.  相似文献   

7.
The alkenylaminoallenylidene complex [Ru(η5-C9H7){CCC(NEt2)[C(Me)CPh2]}{κ(P)-Ph2PCH2CHCH2}(PPh3)][PF6] (2) has been prepared by the reaction of the allenylidene [Ru(η5-C9H7)(CCCPh2){κ(P)-Ph2PCH2CHCH2}(PPh3)][PF6] (1) with the ynamine MeCCNEt2. The reaction proceeds regio- and stereoselectively, and the insertion of the ynamine takes place exclusively at the CβCγ bond of the unsaturated chain. The secondary allenylidene [Ru(η5-C9H7){CCC(H)[C(Me)CPh2]}{κ(P)-Ph2PCH2CHCH2}(PPh3)][PF6] (3) is obtained, in a one-pot synthesis, from the reaction of aminoallenylidene 2 with LiBHEt3 and subsequent treatment with silica. Moreover, the addition of an excess of NaBH4 to a solution of the complex 2 in THF at room temperature gives exclusively the alkynyl complex [Ru(η5-C9H7){CCCH2[C(Me)CPh2]}{κ(P)-Ph2PCH2CHCH2}(PPh3)] (5). The heating of a solution of allenylidene derivative 3 in THF at reflux gives regio- and diastereoselectively the cyclobutylidene complex [Ru(η5-C9H7) (PPh3)][PF6](4) through an intramolecular cycloaddition of the CC allyl and the CαCβ bonds in the allenylidene complex 3. The structure of complex 4 has been determined by single crystal X-ray diffraction analysis.  相似文献   

8.
In contrast to the simple diynyl complexes formed in reactions between HCCCCFc and MCl(dppe)Cp∗; (M = Fe, Ru), an analogous reaction with RuCl(PPh3)2Cp∗; in the presence of KPF6 and dbu resulted in dimerisation of the diyne at the Ru centre to afford a mixture of [Ru{η12-C(CCFc)C(L)CHCCCHFc}(PPh3)Cp∗]PF6 (L = dbu 1, PPh32). Similar reactions with RuCl(PR3)2L gave [Ru{η12-C(CCFc)C(dbu)CHCCCHFc}(PR3)L]PF6 (L = Cp, R = Ph 3, m-tol 4; L = η5-C9H7, R = Ph 5). The reaction between 3 and I2, followed by crystallization of the paramagnetic product from MeOH, afforded the dicationic [Ru{C(CCFc)C(dbu)CHC(OMe)C(OMe)CHFc}(PPh3)Cp](I3)26. The molecular structures of 2·2CH2Cl2 and 6.S (S = 2CH2Cl2, C6H6) were determined by single-crystal XRD studies.  相似文献   

9.
The reaction of the methylidyne-bridged cluster HRu3(CO)10(μ-COMe) (1) with the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) and Me3NO furnishes HRu3(CO)8(μ-COMe)(bpcd) (2) and HRu3(CO)8(Ph2PH)[μ-PPh2CCC(O)CH2C(O)] (3) as the major and minor products, respectively. The 1H and 31P NMR data indicate that the bpcd ligand in 2 is chelated to one of the ruthenium atoms that is bridged by the hydride and methylidyne ligands. Thermolysis of 2 is accompanied by P-Ph bond cleavage and elimination of benzene to yield Ru3(CO)73-COMe)[μ-P(Ph)CC(PPh2)C(O)CH2C(O)] (4). Compound 4 consists of a triangular ruthenium core that is face-capped by μ3-COMe methylidyne and μ-P(Ph)CC(PPh2)C(O)CH2C(O) phosphido ligands. The kinetics for the conversion of 2 → 4 have been measured in toluene solvent over the temperature range 320-343 K, and based on the observed activation parameters and the inhibitory effect of added CO on the reaction, a rate-limiting step involving a dissociative loss of CO is supported. Heating 4 in the presence of H2 afforded the phosphinidene-capped cluster H3Ru3(CO)73-PPh)[μ-CC(PPh2)C(O)CH2C(O)] (5). Crystallographic analysis of 5 has confirmed the loss of the methylidyne moiety and the cleavage of the phosphido PhP-C(dione) bond, and the presence of three edge-bridging hydrides is supported by 1H NMR spectroscopy. The reaction of 4 with added PPh3 and PMe3 has been investigated; the uptake of a single phosphine ligand occurs regiospecifically at one of the phosphido-bound ruthenium centers to give Ru3(CO)6L(μ3-COMe)[μ-P(Ph)CC(PPh2)C(O)CH2C(O)] (PPh3, 6; PMe3, 7). Compound 6 contains 48e- and exhibits a structural motif similar to that found in 4. Compound 7 readily adds a second PMe3 ligand to yield the bis-substituted cluster Ru3(CO)6(PMe3)22-COMe)[μ-P(Ph)CC(PPh2)C(O)CH2C(O)] (8). The solid-state structure of 8 confirms the loss of two ruthenium-ruthenium bonds and the conversion of the original face-capping μ3-COMe ligand to a μ2-COMe moiety that tethers two non-bonding ruthenium centers. The two PMe3 ligands in 8 coordinate to the same ruthenium center, and the 9e- P(Ph)CC(PPh2)C(O)CH2C(O) ligand binds all three ruthenium atoms through the phosphine, phosphido, alkene, and carbonyl moieties. Near-UV irradiation of 8 leads to loss of CO and polyhedral contraction of the triruthenium frame to yield the 48e- cluster Ru3(CO)5(PMe3)23-COMe)[μ-P(Ph)CC(PPh2)C(O)CH2C(O)] (9).  相似文献   

10.
The preparation of several ruthenium complexes containing cyanocarbon anions is reported. Deprotonation (KOBut) of [Ru(NCCH2CN)(PPh3)2Cp]PF6 (1) gives Ru{NCCH(CN)}(PPh3)2Cp (2), which adds a second [Ru(PPh3)2Cp]+ unit to give [{Ru(PPh3)2Cp}2(μ-NCCHCN)]+ (3). Attempted deprotonation of the latter to give the μ-NCCCN complex was unsuccessful. Similar chemistry with tricyanomethanide anion gives Ru{NCC(CN)2}(PPh3)2Cp (4) and [{Ru(PPh3)2Cp}2{μ-NCC(CN)CN}]PF6 (5), and with pentacyanopropenide, Ru{NCC(CN)C(CN)C(CN)2}(PPh3)2Cp (6) and [{Ru(PPh3)2Cp}2{μ-NCC(CN)C(CN)C(CN)CN}]PF6 (7). The Ru(dppe)Cp* analogues of 6 and 7 (8 and 9) were also prepared. Thermolysis of 6 (refluxing toluene, 12 h) results in loss of PPh3 and formation of the binuclear cyclic complex {Ru(PPh3)Cp[μ-NC{C(CN)C(CN)2}CN]}2 (10). The solid-state structures of 2-4 and 8-10 have been determined and the nature of the isomers shown to be present in solutions of the binuclear cations 7 and 9 by NMR studies has been probed using Hartree-Fock and density functional theory.  相似文献   

11.
A series of heterobinuclear ferrocene-ruthenium complexes Fc(CHCH)nRuCl(CO)(PMe3)3 (n = 1, 3; n = 2, 12), Fc(CHCH)RuCl(CO)(Py)(PPh3)2 (4), and trimetallic Fc(CHCH)RuCl(CO)(PPh3)2(Py-E-(CHCH)Fc) (6) have been prepared. The length of the molecular rods is extended by successive insertion of CHCH spacers in the bridging ligands or the ancillary ligands. The respective products have been fully characterized and the structures of 3 and 12 have been established by X-ray crystallography. Electrochemical studies have revealed that ethenyl heterobimetallic complexes display two successive one-electron processes, and that intermetallic electronic communication between the two endgroups is attenuated with the increase of the length of the conjugated bridge. The electrochemical behavior of the trimetallic complex reveals strong electronic communication between ruthenium and ferrocene transmitted through the ethenyl bridge, however, it also reveals a very weak interaction between ruthenium and ferrocene transmitted through the (E)-CHCH-Py bridge.  相似文献   

12.
Facile ligand substitutions are observed when the neutral ruthenium cyclopropenyl complex (PPh3)[Ru]-CC(Ph)CHCN (1, [Ru] = Tp(PPh3)Ru) is treated with MeCN and pyrazole yielding the nitrile substituted ruthenium cyclopropenyl complex (MeCN)[Ru]-CC(Ph)CHCN (4a) and the ruthenium metallacyclic pyrazole complex (C3H3NN)[Ru]-CC(Ph)CH2CN (7a), respectively. The reactions of Me3SiN3 with 1, 4a and 7a are investigated. Treatment of 1 with Me3SiN3 affords in high yield the cationic N-coordinated nitrile complex {(PPh3)[Ru]NCCH(Ph)CH2CN}N3 (3). Interestingly, the reaction of 4a with Me3SiN3 in CH2Cl2 in the presence of NH4PF6 results in an insertion of four nitrogen atoms into the Ru-Cα bond to form a diastereomeric mixture of the bright yellow zwitterionic tetrazolate complex (MeCN)[Ru]-N4CCH(Ph)CH2CN (6a) in a 3:2 ratio. The reaction of 7a with Me3SiN3 gives the zwitterionic tetrazolate complex (C3H3NNH)[Ru]-N4CCH(Ph)CH2CN (9a). The two cationic tetrazolate complexes {(C3H3NNH)[Ru]-N4(R)CCH(Ph)CH2CN}+ (12a, R = CH3, 12b, R = C6H5CH2) are prepared by electrophilic addition of organic halides to 9a. All of the complexes are identified by spectroscopic methods as well as elemental analysis. Pathways for the synthesis of these compounds are proposed.  相似文献   

13.
14.
Hydrosilylation of terminal alkynes with a variety of silanes catalyzed by Cl2(PCy3)2RuCHPh (1) affords mainly the Z-isomer via trans addition in excellent yields. The presence of a hydroxyl group in close proximity to the triple bond was observed to exert a strong directing effect, resulting in the highly selective formation of the α-isomer. Intramolecular hydrosilylation of a homopropargylic silyl ether was demonstrated to give the cis addition product.  相似文献   

15.
The diruthenium μ-allenyl complex [Ru2(CO)(NCMe)(μ-CO){μ-η12-C(H)CC(Me)(Ph)}(Cp)2][BF4], 3b, reacts with halide anions to yield the neutral derivatives [Ru2(CO)2(X){μ-η12-C(H)CC(Me)(Ph)}(Cp)2] [X = Cl, 4b; X = Br, 4c; X = I, 4d]. Complex 4b undergoes isomerization to the unprecedented bridging vinyl-chlorocarbene species [Ru2(CO)(μ-CO){μ-η13- C(Cl)C(H)C(Me)(Ph)}(Cp)2], 10, upon filtration of a CH2Cl2 solution through an alumina column.Complex 3b reacts with an excess of NaBH4 to give five products: the allene complex [Ru2(CO)2{μ-η22- CH2CC(Me)(Ph)}(Cp)2], 5; the hydride species trans-[Ru2(CO)2(μ-H){μ-η12-CHCC(Me)(Ph)}(Cp)2], 6, and cis-[Ru2(CO)2(μ-H){μ-η12-CHCC(Me)(Ph)}(Cp)2], 8; the vinyl-alkylidene [Ru2(CO)(μ-CO){μ-η13- C(H)C(H)C(Me)(Ph)}(Cp)2], 9; and the cluster [Ru3(CO)3(μ-H)3(Cp)3], 7.Studies on the thermal stabilities of 5, 6, 8 and 9 have suggested a plausible mechanism for the formation of these complexes and for the synthesis of 10.  相似文献   

16.
Reactions of Fe2(CO)9 with Cp(CO)2MnCCHPh (1) and Cp(CO)(PPh3)MnCCHPh (3) gave the heterometallic trimethylenemethane complexes η4-{C[Mn(CO)2Cp](CO)CHPh}Fe(CO)3 (2) and η4-{C[Mn(CO)(PPh3)Cp](CO)CHPh}Fe(CO)3 (4), respectively. The formation of the benzylideneketene [PhHCCCO] fragment included in complexes 2 and 4 occurs via intramolecular coupling of the carbonyl and vinylidene ligands. The structures of 3 and 4 were determined by single crystal XRD methods. The influence of the nature of the L ligands at the Mn atom on the structural and spectroscopic characteristics of η4-{C[Mn(CO)(L)Cp](CO)CHPh}Fe(CO)3 (L = CO (2), PPh3 (4)) is considered. According to the VT 1H and 13C NMR spectra, complex 2 reversibly transforms in solution into μ-η11-vinylidene isomer Cp(CO)2MnFe(μ-CCHPh)(CO)4 (2a), whereas complex 4 containing the PPh3 ligand is not able to a similar transformation.  相似文献   

17.
Treatment of the thiosemicarbazones 4-FC6H4C(Me)NN(H)C(S)NHR, (R = Me, a; Ph, b) and 2-ClC6H4C(Me)NN(H)C(S)NHR (R = Ph, c) with lithium tetrachloropalladate(II) in methanol or palladium(II) acetate in acetic acid gave the tetranuclear cyclometallated complex [Pd{4-FC6H3C(Me)NNC(S)NHR}]4 (1a, 1b) and [Pd{2-ClC6H3C(Me)NNC(S)NHPh}]4 (1c). Reaction of these tetramers with the diphosphines dppe, t-dppe, dppp or dppb in a 1:2 molar ratio gave the dinuclear cyclometallated complexes [(Pd{4-FC6H3C(Me)NNC(S)NHR})2(μ-Ph2P(CH2)nPPh2)], (n = 2, 2a, 2b; 3, 4a, 4b; 4, 5a, 5b), [(Pd{4-FC6H3C(Me)NNC(S)NHPh})2(μ-Ph2PCHCHPPh2)], (3a, 3b) and [(Pd{2-ClC6H3C(Me)NNC(S)NHR})2(μ-Ph2P(CH2)nPPh2)], (n = 2, 2c, 2d; 3, 4c, 4d; 4, 5c, 5d), [(Pd{2-ClC6H3C(Me)NNC(S)NHPh})2(μ-PPh2CHCHPPh2)], (3c, 3d). The X-ray crystal structure of the ligand b and the complexes 3c, 4a and 4d were determined. The structures of complexes 4a and 4d show that the different disposition of the chain cyclometallated of the thiosemicarbazones (in the same orientation or in the opposite one) is due to the different H bonds produced.  相似文献   

18.
Several complexes have been obtained from reactions carried out in early attempts to prepare the diynyl complexes Ru(CCCCR)(dppe)Cp* (R = H, SiMe3). These have been identified crystallographically as the acyl complex Ru{CCC(O)Me}(dppe)Cp* (3), the cationic imido complex [Ru{CCC(NH2)Me}(dppe)Cp*]PF6 (4), the binuclear butenynylallenylidene [{Ru(dppe)Cp*}2{μ-CCC(OMe)CHCMeCC}]PF6 (5), and the bis(ethynyl)cyclobutenylidene [{Ru(dppe)Cp*}2{μ-CCC4H2(SiMe3)CC}]PF6 (6). NMR studies of 5 have revealed the existence of two isomers. Plausible routes for their formation from the putative butatrienylidene intermediate [Ru(CCCCH2)(dppe)Cp*]+ (A) are discussed.  相似文献   

19.
Kai-Min Wu 《Tetrahedron》2005,61(41):9679-9687
Three pendant benzamidines [Ph-C(NC6H5)-{NH(CH2)2NMe2}] (1), [Ph-C(NC6H5)-{NH(CH2Py)}] (2) and [Ph-C(NC6H5)-{NH(o-C6H4)(oxazoline)}] (3) are described. Reactions of 1, 2 or 3 with one molar equivalent of Pd(OAc)2 in THF give the palladacyclic complexes [Ph-C{-NH(η1-C6H4)}{N(CH2)2NMe2}]Pd(OAc) (4), [Ph-C{-NH(η1-C6H4)}{N (CH2Py)}]Pd(OAc) (5) and [Ph-C{-NH(η1-C6H4)}{N(o-C6H4)(oxazoline)}]Pd(OAc) (6), respectively. Treatment of 4, 5 or 6 with excess of LiCl in chloroform affords [Ph-C{-NH(η1-C6H4)}{N(CH2)2NMe2}]PdCl (7), [Ph-C{-NH(η1-C6H4)}{N(CH2Py)}]PdCl (8) and [Ph-C{-NH(η1-C6H4)}{N(o-C6H4)(oxazoline)}]PdCl (9). The crystal and molecular structures are reported for compounds 1, 3, 5, 6 and 7. The application of these palladacyclic complexes to the Suzuki and Heck coupling reactions was examined.  相似文献   

20.
The novel bis(iminophosphorano)methanes CH2[P{NP(S)(OR)2}Ph2]2 (R = Ph (1a), Et (1b)) have been obtained by oxydation of dppm with the corresponding thiophosphorylated azides (RO)2P(S)N3. Deprotonation of 1a,b with KH generates the methanide species KCH[P{NP(S)(OR)2}Ph2]2 (R = Ph (2a), Et (2b)). The ruthenium(II) dimer [{Ru(η6-p-cymene)(μ-Cl)Cl}2] reacts with 2a,b to afford the cationic complexes [Ru(η6-p-cymene)(κ3-C,N,S-CH[P{NP(S)(OR)2}Ph2]2)]+ (R = Ph (3a), Et (3b)), via selective κ3-C,N,S-coordination of the bis(iminophosphorano)methanide anions to ruthenium. The structure of [Ru(η6-p-cymene)(κ3-C,N,S-CH[P{NP(S)(OEt)2}Ph2]2)][PF6] (3b) has been confirmed by single-crystal X-ray crystallography. Deprotonation of complexes 3a,b with NaH leads to the neutral carbene derivatives [Ru(η6-p-cymene)(κ2-C,N-C[P{NP(S)(OR)2}Ph2]2)] (R = Ph (4a), Et (4b)).  相似文献   

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