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1.
Reaction of lithium diisopropylamide (LDA) with (η4-1,3-cyclohexadiene)Fe(CO)3 complexes bearing functionalized side chains at C-5, under an atmosphere of carbon monoxide, gives bridged bicyclo[3,2,1]octene and bicyclo[3,3,1]nonene systems after electrophilic quenching. Under the same reaction conditions, intramolecular cyclization of acyclic (η4- 1,3-butadiene)Fe(CO)3 complexes with functionalized side chains at the terminal position of the diene ligands furnishes fused bicyclo[3.3,0]octanone and bicyclo[4.3.0]nonanone derivatives after acid quenching. The addition of a variety of the highly functionalized zinc-copper reagents RCu(CN)ZnI to the (η7-cycloheptatrienyl)Cr(CO) gives (η6-cyclohepta-1,3,5-triene)Cr(CO)3 complexes with a functionalized side-chain at the C-7 position of the ring. Intramolecular cyclization of ester-subsbtuted adducts using lithium diisopropylamide generates fused bicyclo[5.3.0]decane and bicyclo[5.4.0]undecane derivatives. The addition of a variety of the highly functionalized zinc-copper reagents RCu(CN)Znl to the (η4-cyclohexa-1,3-diene)Mo(CO)2(Cp) at the terminus of the coordinated diene ligand gives [Mo(π-allyl)(CO)2(Cp)](Cp = cyclopentadienyl) complexes with the functionalized side-chain at the C-4 position of the ring. Intramolecular cyclization of the (π-allyl)molybdenum complex containing a pendant propanoic acid unit generates the δ-lactone derivative. 相似文献
2.
Regioselectivity of the addition of the highly functionalized zinc-copper reagents to (η3-allyl)Fe(CO)4 cationic salts was studied. For 1,1-disubstituted allyl cation 1, the zinc-copper reagents added predominantly at the unsubstituted terminus. For 1,1,2-trisubstituted allyl cation 2, reactive zinc-copper reagents attacked mainly at the unsubstituted terminus while less reactive zinc-copper reagents added to a coordinated CO ligand. For 1,1,3-trisubstituted allyl cation 3, the addition occurred at both the less substituted allyl terminus and a coordinated CO ligand. 相似文献
3.
G. Doyle 《Journal of organometallic chemistry》1977,132(2):243-254
Anionic complexes of the type [M(CO)2(diket)(η3-allyl)Cl]? (where M is Mo or W and diket is a β-diketonate group) are readily prepared by the addition of allyl chloride to [M(CO)4(diket)]? anions. NMR measurements indicate an equilibrium between two conformers due to rotation of the allyl groups. [M(CO)5(OC(=O)R)]? anions also react with allyl chloride to form η3-allyl complex anions. Some structural aspects of both the diketonate and carboxylate derivatives are discussed. 相似文献
4.
Dr. Dolores Morales Marcos Puerto Dr. Ignacio del Río Dr. Julio Pérez Dr. Ramón López 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(50):16186-16195
The labile complex [MoCl(η3‐methallyl)(CO)2(NCMe)2] reacts with the ligand 1,4,7‐trithiacyclononane ([9]aneS3) and the salt NaBAr′4 to afford [Mo(η3‐methallyl)(CO)2([9]aneS3)][BAr′4] ( 1?BAr′4 ). An analogous reaction of [MoBr(η3‐allyl)(CO)2(NCMe)2] yields [Mo(η3‐allyl)(CO)2([9]aneS3)][BAr′4] ( 2?BAr′4 ). The new compounds 1?BAr′4 and 2?BAr′4 were characterized by IR and NMR spectroscopic analysis and X‐ray diffraction studies. Both compounds feature the cyclic thioether [9]aneS3 coordinated as a tridentate ligand to the molybdenum center. The allyl ligand in 2?BAr′4 is aligned with the middle of the OC‐Mo‐CO angle, which is acute. Both of these features are typical of most pseudo‐octahedral allyl dicarbonyl molybdenum complexes. In contrast, the allyl group is rotated in 1?BAr′4 , which is attributed to steric hindrance between the methyl substituent and the ligated thioether, and the OC‐Mo‐CO angle is obtuse. Compound 1?BAr′4 undergoes rapid substitution of [9]aneS3 by either chloride and fluoride ions in dichloromethane, and the products include the known species [{Mo(η3‐methallyl)(CO)2}2(μ‐Cl)3]? and a structurally similar new anionic complex with two fluoro and one hydroxo bridging ligands, respectively. Stable supramolecular adducts were formed in the reactions of 1?BAr′4 and 2?BAr4 with bromide, iodide, hydrogensulfate, and methanesulfonate compounds. The binding constants of these adducts in dichloromethane were calculated from 1H NMR spectroscopic titration data, and the solid‐state structures of the 1?Br , 1?HSO4 , 1?I , and 2?I adducts were determined by X‐ray diffraction studies. The surprising slightly higher stability of the iodide adduct relative to that of bromide was investigated theoretically, with the results pointing to an effect of the differential solvation of the halide ions. 相似文献
5.
Arroyo M Miguel D Villafañe F Alegria EC Pombeiro AJ 《Dalton transactions (Cambridge, England : 2003)》2012,41(23):7017-7025
Molybdenum and tungsten complexes containing the pypzH (3-(2-pyridyl)pyrazole) ligand as a chelating bidentate are prepared: [Mo(CO)(4)(pypzH)], cis-[MoBr(η(3)-allyl)(CO)(2)(pypzH)], cis-[MoCl(η(3)-methallyl)(CO)(2)(pypzH)], [MI(2)(CO)(3)(pypzH)] (M = Mo, W) from [Mo(CO)(4)(NBD)] or the adequate bis(acetonitrile) complexes. The deprotonation of the molybdenum allyl or methallyl complexes affords the bimetallic complexes [cis-{Mo(η(3)-allyl)(CO)(2)(μ(2)-pypz)}](2) or [cis-{Mo(η(3)-methallyl)(CO)(2)(μ(2)-pypz)}](2) (μ(2)-pypz = μ(2)-3-(2-pyridyl-κ(1)N)pyrazolate-2κ(1)N). The allyl complex was subjected to an electrochemical study, which shows a marked connection between both metallic centres through the bridging pyridylpyrazolates. 相似文献
6.
Oussama M. El-Kadri 《Journal of organometallic chemistry》2009,694(24):3902-2564
Treatment of M(allyl)(Cl)(CO)2(py)2 (M = Mo, W) with 1 equiv. of potassium pyrazolates in tetrahydrofuran at −78 °C afforded M(allyl)(R2pz)(CO)2(py)n (R2pz = 3,5-disubstituted pyrazolate; n = 1, 2) in 68-81% yields. X-ray crystal structure analyses of Mo(allyl)((CF3)2pz)(CO)2(py)2 and W(allyl)(tBu2pz)(CO)2(py) revealed η1- and η2-coordination of the (CF3)2pz and tBu2pz ligands, respectively. Analogous treatment of Mo(allyl)(Cl)(CO)2(NCCH3)2 with 1 equiv. of tBu2pzK in tetrahydrofuran at −78 °C afforded [Mo(allyl)(tBu2pz)(CO)2]2 in 79% yield. An X-ray crystal structure analysis of [Mo(allyl)(tBu2pz)(CO)2]2 showed a dimeric structure bridged by two μ-η2:η1-tBu2pz ligands. Treatment of M(allyl)(Cl)(CO)2(py)2 with 1 equiv. of lithium 1,3-diisopropylacetamidinate or lithium 1,3-di-tert-butylacetamidinate in diethyl ether at −78 °C afforded M(allyl)(iPrNC(Me)NiPr)(CO)2(py) and M(allyl)(tBuNC(Me)NtBu)(CO)2(py), respectively, in 68-78% yields. The new complexes were characterized by spectral and analytical methods and by X-ray crystal structure determinations. M(allyl)(iPrNC(Me)NiPr)(CO)2(py) adopt pseudo-octahedral geometry about the metal centers, with the 1,3-diisopropylacetamidate ligand nitrogen atoms spanning one axial site and one equatorial site of the octahedron. By contrast, M(allyl)(tBuNC(Me)NtBu)(CO)2(py) adopt pseudo-octahedral structures in which the two 1,3-di-tert-butylacetamidinate ligand nitrogen atoms span two equatorial coordination sites. Sublimation of M(allyl)(tBuNC(Me)NtBu)-(CO)2(py) at 105 °C/0.03 Torr afforded ?7% yields of M(allyl)(tBuNC(Me)NtBu)(CO)2, along with sublimed M(allyl)(tBuNC(Me)NtBu)(CO)2(py). W(allyl)(tBuNC(Me)NtBu)(CO)2 exists in the solid state as a 16-electron complex with distorted square pyramidal geometry. Many of the new complexes undergo dynamic ligand site exchange in solution, and these processes were probed by variable temperature 1H NMR spectroscopy. The volatilities and thermal stabilities were evaluated to determine the potential of the new complexes for use as precursors in thin film growth experiments. 相似文献
7.
The complexes [MBr(π-allyl)(CO)2(bipy)] (M = Mo, W, bipy = 2,2′-bipyridine) react with alkylxanthates (MIRxant), and N-alkyldithiocarbamates (MIRHdtc) (MI = Na or K), yielding complexes of general formula [M(S,S)- (π-allyl)(CO)2(bipy)] (M = Mo, (S,S) = Rxant (R = Me, Et, t-Bu, Bz), RHdtc (R = Me, Et); M = W, (S,S) = Extant). A monodentate coordentate coordination of the (S,S) ligand was deduced from spectral data. The reaction of [MoBr(π-allyl)(CO)2(bipy)] with MeHdtc and Mexant gives the same complexes whether pyridine is present or not. The complexes [Mo(S,S)(π-allyl)(CO)2(bipy)] ((S,S) = MeHdtc, Mexant) do not react with an excess of (S,S) ligand and pyridine.No reaction products were isolated from reaction of [MoBr(π-allyl)(CO)2(dppe)] with xanthates or N-alkyldithiocarbamates. 相似文献
8.
《Journal of organometallic chemistry》1987,326(1):C13-C16
It is shown that (1,2,7-η3-2-Me-benzyl)(η5-C5H5)Mo(CO)2 exits in solution as one isomer which is fluxional, probably via (7-η1-2-Me-benzyl)((η5-C5H5)Mo(CO)2, with ΔG≠370 = 23.6 ± 1.0 kcal mol−1. In contrast, (1,2,7-η3-3-Me-benzyl)(η5-C5H5)Mo(CO)2 exits as two isomers at −20°C, which undergo interconversion at room temperature with ΔG≠ 15.7 kcal mol−1. This dynamic process is an allyl rotation. It is probable that there is also a low energy [1,5]-sigmatropic shift. 相似文献
9.
Silver tetrafluoroborate reacts with Cl(bipy)(CO)2(η3-C3H5)Mo in CH2Cl2 to give the dimeric cation, (μ-Cl)[(bipy)(CO)2(η3-C3H5)Mo]2+, isolated as the crystalline BF4? salt with CH2Cl2 of solvation (5). Complex 5 crystallizes in the triclinic system (space group P, No. 2) with cell parameters: a 11.831(2), b 10.142(3), c 15.618(3) Å; α 93.96(2), β 104.33(2), γ 91.41(2)°, V 1809.5(8) Å3Z = 2, ?calc 1.60 g cm?3. Full matrix refinement with all but three atoms anisotropic converged at R1 = 0.057 and R2 = 0.073 based on 3742 reflections with I > 30(1). The two halves of the dimer are connected by a single chloride bridge (Mo-Cl 2.554(3), 2.519(3) Å, Mo-Cl-Mo 134.0(1)°). The η3-allyl group is oriented so that its open face points toward the two cis-carbonyl groups, a feature common to all L2X(CO)2Mo(η3-allyl) structures determined to date. A molecular orbital analysis shows that this rotational preference of the allyl group has its roots in the strong π-bonding character of the carbonyls. The MO analysis also provides a rationale for regioselectivity observed in the reactions of various η3-allyl complexes with nucleophiles. In particular, the factors which determine whether the terminal carbons are attacked (giving olefin) or whether the central carbon is attacked (giving a metallacyclobutane) are exposed. 相似文献
10.
G. Doyle 《Journal of organometallic chemistry》1978,150(1):67-73
A number of complexes of the type M(CO)2(η3-allyl)(diket)L (where M is Mo or W, diket is a β-diketonate group and L is pyridine, tetrahydofuran or acetonitrile) have been prepared and characterized by elemental analysis and IR and NMR spectroscopy. These complexes apparently adopt an octahedral configuration similar to related neutral species but spectroscopic data indicate an equilibrium between two conformers probably due to rotation of the allyl groups. 相似文献
11.
Karlheinz Sünkel Günter Urban Wolfgang Beck 《Journal of organometallic chemistry》1983,252(2):187-194
In the tetrafluoroborato complexes (η5-C5H5)(CO)2LMFBF3 (M = Mo, W; L = CO, PPh3, P(OPh)3) and (η5-C9H7)(CO)3WFBF3 the coordinated fluorine atom and the terminal F atoms of the BF4 ligand can be distinguished by their 19F NMR signals. 19F and 31P NMR spectra of (η5-C5H5)(CO)2P(OPh)3WFBF3 allow to establish cis → trans isomerization at elevated temperatures as well as rapid rotation of the coordinated BF4 ligand. 相似文献
12.
Jan Honzí?ek Abhik Mukhopadhyay Carlos C. Romão 《Journal of organometallic chemistry》2010,695(5):680-2319
The synthesis of new cyclopenta[l]phenanthrenyl complexes [(η5-C17H10Me)(η3-C3H5)Mo(CO)2] and [(η5-C17H9(COOMe)N(CH2)4)(η3-C3H5)Mo(CO)2] is described. Although these compounds are structural analogues their reactivity is different. Protonation of [(η5-C17H10Me)(η3-C3H5)Mo(CO)2] gives a stable ionic compound [(η5-C17H10Me)Mo(CO)2(NCMe)2][BF4] while its analogue containing both tertiary amino and carboxylic ester groups [(η5-C17H9(COOMe)N(CH2)4)(η3-C3H5)Mo(CO)2] decomposes under the same conditions. [(η5-C17H10Me)Mo(CO)2(NCMe)2][BF4] reacts with cyclopentadiene to give a stable η4-complex [(η4-C5H6)(η5-C17H10Me)Mo(CO)2][BF4] that was successfully oxidized to the Mo(IV) dicationic compound [(η5-C5H5)(η5-C17H10Me)Mo(CO)2][Br][BF4]. 相似文献
13.
Yamaguchi Y Ogata K Kobayashi K Ito T 《Dalton transactions (Cambridge, England : 2003)》2004,(23):3982-3990
The reactivity of amidinato complexes of molybdenum and tungsten bearing pyridine as a labile ligand, [M(eta(3)-allyl)(eta(2)-amidinato)(CO)(2)(pyridine)](M = Mo; 1-Mo, M = W; 1-W), toward bidentate ligands such as 1,10-phenanthroline (phen) and 1,2-bis(diphenylphosphino)ethane (dppe) was investigated. The reaction of 1 with phen at ambient temperature resulted in the formation of monodentate amidinato complexes, [M(eta(3)-allyl)(eta(1)-amidinato)(CO)(2)(eta(2)-phen)](M = Mo; 2-Mo, M = W; 2-W), which has pseudo-octahedral geometry with the amidinato ligand coordinated to the metal in an eta(1)-fashion. The phen ligand was located coplanar with two CO ligands and the eta(1)-amidinato ligand was positioned trans to the eta(3)-allyl ligand. In solution, both complexes 2-Mo and 2-W showed fluxionality, and complex 2-Mo afforded allylamidine (3) on heating in solution. In the reaction of 1 with dppe at ambient temperature, the simple substitution reaction took place to give dppe-bridged binuclear complexes [{M(eta(3)-allyl)(eta(2)-amidinato)(CO)(2)}(2)(mu-dppe)](M = Mo; 5-Mo, M = W; 5-W), whereas mononuclear monocarbonyl complexes [M(eta(3)-allyl)(eta(2)-amidinato)(CO)(eta(2)-dppe)](M = Mo; 6-Mo, M = W; 6-W) were obtained under acetonitrile- or toluene-refluxing conditions. Mononuclear complex 6 was also obtained by the reaction of binuclear complex 5 with 0.5 equivalents of dppe under refluxing in acetonitrile or in toluene. The X-ray analyses and variable-temperature (31)P NMR spectroscopy of complex 6 indicated the existence of the rotational isomers of the eta(3)-allyl ligand, i.e., endo and exo forms, with respect to the carbonyl ligand. The different reactivity of complex 1 toward phen and dppe seems to have come from the difference in the pi-acceptability of each bidentate ligand. 相似文献
14.
Piotr Smoleński 《Journal of organometallic chemistry》2011,696(24):3867-3872
Reactions of [(η5-R)Rh(CO)2] (R = cp, ind) with water-soluble phosphines (L = 1,3,5-triaza-7-phosphaadamantane and tris(2-cyanoethyl)phosphine) give the new rhodium(I) complexes of the types [Rh(η5-cp)(CO)(PTA)] (1), [Rh(η5-cp)(CO)(P(CH2CH2CN)3)] (2), [Rh(η5-ind)(CO)(PTA)] (3) and [Rh(η5-ind)(CO)(P(CH2CH2CN)3)] (4) in isolated yields of 52-75%. All these compounds have been fully characterized by IR, 1H, 31P{1H} and 13C{1H} NMR, FAB-MS spectroscopies and elemental analyses. Reactivity for the substitution of phosphine is greater for [(η5-ind)Rh(CO)(L)] comparing to [(η5-cp)Rh(CO)(L)] because of a flexibility of the indenyl ligand to undergo facile η5-η3 coordinative isomerizations. The obtained complexes are active catalyst precursors for the dehydrogenation of propan-2-ol, octane and cyclooctane under photoassisted conditions without any organic hydrogen transfer acceptors, giving TOFs of 26-56 using 3 as precatalyst. 相似文献
15.
Ayfer Mentes Raymond D.W KemmittJohn Fawcett David R Russell 《Journal of organometallic chemistry》2002,660(1):91-97
Treatment of the molybdenum tetracarbonyl complexes of [Mo(CO)4L2] (L2=pyridyl amine Schiff base ligands) with allyl chloride in refluxing THF afforded η3-allyl complexes [MoCl(CO)2L2(η3-allyl)] (1-9). These complexes have been characterised by various techniques including 1H-NMR, IR and FABMS spectroscopies and the single crystal X-ray structure determinations of the complexes [MoCl(CO)2{N(C6H4-2-OMe)C(Me)C5H4N}(η3-C3H5)] (3) and [MoCl(CO)2{N(Me)C(Ph)C5H4N}(η3-C3H5)] (4). 相似文献
16.
《Journal of organometallic chemistry》1987,331(2):229-238
The reactivity of the (η5-formylcyclopentadienyl)M(CO)3 anions (M Mo, W) towards acyl chlorides has been studied. Acetyl chloride reacts with the anions to give two different types of substituted cyclopentadienyl complexes: [M(Cl)(η5-C5H4CH2OC(O)CH3)(CO)3] and [M(η1-CH3CO)(η5-CH3CO)(η5-C5H4CH2OC(O)CH3)(CO)3]. The reaction of the anions with benzoyl chloride only yields the chloro complexes [M(Cl)(η5-C5H4CH2OC(O)C6H5)(CO)3]. The molecular structure of [W(Cl)(η5-C5H4CH2OC(O)CH3)(CO)3] has been determined by X-ray diffraction studies. 相似文献
17.
A novel, useful in situ synthesis for NHC nickel allyl halide complexes [Ni(NHC)(η3-allyl)(X)] starting from [Ni(CO)4], NHC and allyl halides is presented. The reaction of [Ni(CO)4] with (i) one equivalent of the corresponding NHC and (ii) with an excess of the corresponding allyl chloride at room temperature leads with elimination of carbon monoxide to complexes of the type [Ni(NHC)(η3-allyl)(X)]. This approach was used to synthesize the complexes [Ni(tBu2Im)(η3-H2C -C (Me)-C H2)(Cl)] ( 2 ), [Ni(iPr2ImMe)(η3-H2C -C (Me)-C H2)(Cl)] ( 3 ), [Ni(iPr2Im)(η3-H2C -C (Me)-C H2)(Cl)] ( 4 ), [Ni(iPr2Im)(η3-H2C -C (H)-C (Me)2)(Br)] ( 5 ), [Ni(Me2ImMe)(η3-H2C -C (Me)-C H2)(Cl)] ( 6 ), and [Ni(EtiPrImMe)(η3-H2C -C (Me)-C H2)(Cl)] ( 7 ). The complexes 1 to 7 were characterized using NMR and IR spectroscopy and elemental analysis, and the molecular structures are provided for 2 and 7 . The allyl nickel complexes 1 – 7 are stereochemically non-rigid in solution due to (i) NHC rotation about the nickel-carbon bond, (ii) allyl rotation about the Ni–η3-allyl axis and (iii) π–σ–π allyl isomerization processes. The allyl halide complexes can be methylated as was demonstrated by the methylation of a number of the complexes [Ni(NHC)(η3-allyl)(X)] with methylmagnesium chloride or methyllithium, which led to isolation of the complexes [Ni(Me2Im)(η3-H2C -C (Me)-C H2)(Me)] ( 8 ), [Ni(tBu2Im)(η3-H2C -C (Me)-C H2)(Me)] ( 9 ), [Ni(iPr2ImMe)(η3-H2C -C (Me)-C H2)(Me)] ( 10 ), [Ni(iPr2Im)(η3-H2C -C (Me)-C H2)(Me)] ( 11 ), [Ni(iPr2Im)(η3-H2C -C (H)-C (Me)2)(Me)] ( 12 ), and [Ni(EtiPrImMe)(η3-H2C -C (Me)-C H2)(Me)] ( 13 ). These complexes were fully characterized including X-ray molecular structures for 10 and 11 . 相似文献
18.
Wolfgang A. Herrmann Jose Gimeno Josef Weichmann Manfred L. Ziegler Barbara Balbach 《Journal of organometallic chemistry》1981,213(2):C26-C30
Photolysis of diphenylketene in the presence of pentacarbonyliron yields the π-allyl/σ-acyl type compound [η3:η1-(C6H5)2CCO)Fe(CO)3 (III) the molecular structure of which has been established by means of X-ray diffraction techniques. Metal-centered carboncarbon bond breaking and bond making in III is evident from 13CO labelling and crossover experiments. The dinuclear compound IV, structurally characterized by the π-allyl/σ-aryl/π-olefin hydrocarbon ligand CH(C6H4)C6H5, is formed upon irreversible decarbonylation of the ketene precursor III. 相似文献
19.
《Journal of organometallic chemistry》1987,320(2):C16-C18
[(η5-C5H5)2Mo(η3-C3H5)]+ [p-CH3C6H4SO3]− is conveniently synthesized by the reaction of (η5-C5H5)2MoH2 with allyl alcohol in the presence of p-toluene sulfonic acid, the mechanism of which is explained by the electrophilic cleavage of the allylO bond of the coordinated allyl alcohol. 相似文献
20.
Marcin Palusiak Bogna Rudolf Arno Pfitzner S?awomir J. Grabowski 《Journal of organometallic chemistry》2006,691(15):3232-3238
The crystal structures of (η5-C5H5)W(CO)3(η1-N-maleimidato) and (η5-C5H5)Fe(CO)2(η1-N-maleimidato) complexes were determined by single crystal X-ray diffraction. The molecular geometries of both structures are compared with those of the Mo analog of the W complex and ethyl-N-maleimide in order to find a relation between the geometrical features and the rate constants of the addition reaction of the sulfhydryl group of biomolecules to the ethylenic bond of the maleimidato fragment. For a deeper insight into the problem DFT calculation were performed. An analysis of atomic charges, using the CHELPG scheme, and of theoretical electron density function, using the AIM theory, was performed. In the (η5-C5H5)W(CO)3(η1-N-maleimidato), likewise in its Mo analog, the carbonyl?carbonyl interaction was found both for experimental and calculated structures. It is probably the first approach to explain this type of intramolecular interactions acting in organometallic compounds. This interaction can play the essential role in the reaction mechanism of nucleophilic addition to the maleimidato moiety. The AIM investigations indicate also the differences in the character of bonding between the η-N-maleimidato ligand and the central metal atom. 相似文献