Synthesis and X-ray crystal structures of the cyclic oxacarbene complexes (n = 1 or 2): boat conformation of the 2-oxacyclohexylidene ligand

Beddoes, Roy L.; Grime, Richard W.; Hussain, Zafar I.; Whiteley, Mark W.

doi:10.1016/s0022-328x(96)06585-0

Cited by 20 publications

(16 citation statements)

References 18 publications

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“…We also consider the oxacarbene ligand, CCH 2 CH 2 CH 2 O, whose complexation with Mo and Ru has been studied previously. 21,27 Figure 7 shows the LUMO orbitals for these ligands, and it is immediately apparent that the calculated orientation follows experimental observations. Thus, we find that for odd numbers of carbon centers the favored orientation has the dCR 2 plane (57) Pipek, J.; Mezey, P. G. J.…”

Section: Allows a Comparison Of Spectroscopic And Structural Data Bot...mentioning

confidence: 52%

“…An extensive chemistry of carbene, vinylidene, and allenylidene complexes of d 6 group 8 metal auxiliaries ML 2 (η-C x H y ) (M = Fe, L 2 = dppe, C x H y = Cp, Cp*; , M = Ru, L 2 = 2PR 3 , dppe, C x H y = Cp, – indenyl (C 9 H 7 ) – ) has been developed on the basis of the reaction of metal halide precursor complexes [MXL 2 (η-C x H y )] with terminal alkynes HCCR in methanol in the presence of a halide acceptor such as NH 4 [PF 6 ] or K[PF 6 ]. The method depends upon ionization of the halide ligand and subsequent addition of the alkyne to the metal center; the lability of the halide to dissociation exhibits a strong dependence upon the identity of the ML 2 (η-C x H y ) auxiliary, with [FeCl(dppe)Cp*] being reactive at ambient temperature while [RuCl(PPh 3 ) 2 Cp] generally requires reflux conditions for the reaction to proceed .…”

Section: Resultsmentioning

confidence: 99%

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Metallacumulenylidene Complexes in the Cycloheptatrienyl Molybdenum Series [Mo{(C)_n═CR₂}L₂(η-C₇H₇)]⁺ (n = 0−2; L₂ = P-Donor Ligand). X-ray Crystal Structures of [Mo{C═C(H)Ph}{P(OMe)₃}₂(η-C₇H₇)][BF₄] and [Mo(C═C═CPh₂)(dppe)(η-C₇H₇)][PF₆] and DFT Investigation of Cumulenylidene Ligand Orientations

et al. 2008

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A series of metallacumulenylidene complexes of the cycloheptatrienyl molybdenum auxiliary [Mo{(C) n CR2}L2(η-C7H7)]+ (n = 0−2; L2 = P-donor ligand) have been synthesized by reaction of [MoXL2(η-C7H7)] (X = Br, L2 = Ph2PCH2CH2PPh2 (dppe); X = I, L2 = 2P(OMe)3) or [Mo(OCMe2)L2(η-C7H7)]+ (L2 = dppe, Ph2PCH2PPh2 (dppm)) with the terminal alkynes HCCR; use of [MoBr(dppe)(η-C7H7)] as a precursor is facilitated by an improved, one-step synthesis from [MoBr(CO)2(η-C7H7)]. Syntheses of the 2-oxacyclocarbene complexes [Mo(CCH2CH2(CH2) x O)L2(η-C7H7)]+ (x = 1, L2 = dppm (1), dppe (2); x = 2, L2 = dppm (3), L2 = dppe (4)), the vinylidenes [Mo{CC(H)(CH2)2CH2OH}(dppe)(η-C7H7)][PF6] (5), [Mo{CC(H)(CH2)xPh}(dppe)(η-C7H7)]+ (x = 2 (6), 1 (7)), and [Mo{CC(H)Ph}{P(OMe)3}2(η-C7H7)]+ (8), and the first examples of monometallic molybdenum allenylidene complexes, [Mo(CCCRPh)(dppe)(η-C7H7)]+ (R = Ph (9), Me (10)) are reported. X-ray structural studies on complexes 8 and 9 have determined Mo−Cα distances as follows: 8, 1.929(3) Å; 9, 1.994(3) Å. In 8, the vinylidene ligand substituents lie in the pseudo mirror plane of the MoL2(η-C7H7) auxiliary (vertical orientation) with the phenyl group located syn to the cycloheptatrienyl ring, whereas the allenylidene ligand substituents of 9 are perpendicular to the pseudo mirror plane (horizontal orientation). This series of atypical orientations of cumulenylidene ligand substituents, imposed by the cycloheptatrienyl molybdenum auxiliary, has been investigated further by variable-temperature NMR spectroscopy and quantum-chemical theoretical calculations. A DFT analysis of the complexes [Mo(CCH2)(dppe)(η-C7H7)]+ (11), [Ru(CCH2)(dppe)Cp]+ (12), and [Mo(CCCMePh)(dppe)(η-C7H7)]+ (10) concurs with experimentally determined cumulenylidene ligand orientations. A separate analysis of the fragments [Mo(dppe)(η-C7H7)]+ and [Ru(dppe)Cp]+ reveals that the HOMO of the [Mo(dppe)(η-C7H7)]+ fragment includes a significant contribution from the metal d z 2 orbital, whereas the HOMO of the [Ru(dppe)Cp]+ fragment is based on a metal d xy orbital, orthogonal to the HOMO of the [Mo(dppe)(η-C7H7)]+ unit. In cumulenylidene complexes of the Mo(dppe)(η-C7H7) auxiliary, interactions between the d z 2 -based HOMO of the metal fragment and the vacant LUMO of the cumulenylidene ligand dominate the control of ligand orientation and thus account for the observed structures.

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Section: Allows a Comparison Of Spectroscopic And Structural Data Bot...mentioning

confidence: 52%

Section: Resultsmentioning

confidence: 99%

Metallacumulenylidene Complexes in the Cycloheptatrienyl Molybdenum Series [Mo{(C)_n═CR₂}L₂(η-C₇H₇)]⁺ (n = 0−2; L₂ = P-Donor Ligand). X-ray Crystal Structures of [Mo{C═C(H)Ph}{P(OMe)₃}₂(η-C₇H₇)][BF₄] and [Mo(C═C═CPh₂)(dppe)(η-C₇H₇)][PF₆] and DFT Investigation of Cumulenylidene Ligand Orientations

et al. 2008

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“…Alternatively, the reaction of 1 with 4-pentyn-1-ol in 1,2-dichloroethane yields the carbene complex [Cp*RuC{O(CH 2 ) 3 CH 2 }( i Pr 2 PNHPy)][PF 6 ] ( 5 ). This species results from the intramolecular nucleophilic attack of the OH group at the C α −C β bond of an intermediate hydroxyvinylidene complex, a process that is well precedented in the literature. ,, …”

Section: Resultsmentioning

confidence: 94%

“…This species results from the intramolecular nucleophilic attack of the OH group at the C R -C β bond of an intermediate hydroxyvinylidene complex, a process that is well precedented in the literature. 10,27,28 Complexes 2-5 display the spectral properties anticipated for allenylidene, vinylidene, and carbene complexes, respectively, being unexceptional. One strong band in the IR spectrum of 2 at 1916 cm -1 is ascribed to the ν(CdCdC) stretching of the cumulated carbon-carbon bonds.…”

Section: Resultsmentioning

confidence: 99%

Nucleophilic Addition Reactions to Allenylidene Complexes of Ruthenium Bearing Hemilabile P,N Ligands: Isolation of the Vinylcarbene Complex [Cp*Ru═CHCH═CPh₂(ⁱPr₂PNHPy)][PF₆]

et al. 2011

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The complex [Cp*RudCdCdCPh 2 ( i Pr 2 PNHPy)][PF 6 ] (2), prepared by reaction of [Cp*Ru(MeCN)-( i Pr 2 PNHPy)][PF 6 ] (1) with HCtCC(OH)Ph 2 , reacts with primary amines, furnishing the corresponding vinylaminocarbenes, which are better formulated as the azoniabutadienyl derivatives [Cp*Ru{C(NHR)-CHdCPh 2 }( i Pr 2 PNHPy)][PF 6 ] (R = Cy (6a), Me (6b), CH 2 CtCH (6c)). These species result from the nucleophilic attack of the amine at the C R atom of the allenylidene ligand. At variance with this, the reaction of 2 with cyclic secondary amines such as piperidine, pyrrolidine, and morpholine yields the Schrock-type vinylcarbene complex [Cp*RudCHCHdCPh 2 ( i Pr 2 PNHPy)][PF 6 ] (7), which has been unequivocally characterized by X-ray structure analysis. This vinylcarbene complex is presumably formed by addition of the cyclic amine to the C γ atom of the allenylidene through the intermediacy of a vinylidene complex. This intermediate vinylidene undergoes a retro-metallo-ene rearrangement, generating 7 plus the product of dehydrogenation of the amine. The reaction of 2 with thiophenol or pentafluorothiophenol afforded the thiocarbenes [Cp*Ru{C(SC 6 R 5 )CHdCPh 2 }( i Pr 2 PNHPy)][PF 6 ] (R = H (8H), F (8F)), which have been structurally characterized. Alternatively, the reaction of 2 with pyridine-2-thiol or pyrimidine-2-thiol leads to the thiocarbenes [Cp*). In these compounds a new five-membered chelate ring has formed, and the i Pr 2 NHPy ligand exhibits hemilabile character, changing its coordination mode from κ 2 P,N to κ 1 P.

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“…The Ru–C(33) bond distance is 1.948(4) Å and comparable to other oxacycloalkylidene ruthenium complexes. For instance, the RuC bond distances in [RuCp(dppe)(C 4 H 6 O)] + and [RuCp(dppe)(C 5 H 8 O)] + featuring five- and six-membered oxacyclocarbene ligands are 1.92(1) and 1.938(4) Å, respectively . The Ru(1)–P(1) and Ru(1)–C(10) bond lengths are 2.3534(10) and 1.952(5) Å.…”

Section: Resultsmentioning

confidence: 99%

Preparation, Characterization, and Reactivity of Azido Complex Containing a Tp(^tBuNC)(PPh₃)Ru Fragment and Ruthenium-Catalyzed Cycloaddition of Organic Azides with Alkynes in Organic and Aqueous Media

Lo¹,

Wang²,

Lee³

et al. 2012

Organometallics

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Treatment of the TpRu complex (PPh 3 )[Ru]-Cl (1, [Ru] = Tp( t BuNC)Ru) with an excess of sodium azide affords the yellow ruthenium azido complex (PPh 3 )[Ru]-N 3 (2). The triazolato complexes (PPh 3 )[Ru]-N 3 C 2 (R) 2 (3a, R = Me; 3b, R = Et) are synthesized via [3+2] cycloadditions of 2 with RO 2 CCCCO 2 R. Complete characterization of these triazolato complexes elucidates the structures and establishes the N(2)-bonding type of the addition products. Alkylation of 3a with organic bromides causes cleavage of the Ru−N bond and affords 1,4,5-trisubstituted triazoles. Moreover, addition of CS 2 to 2 produces thermally unstable thiothiatriazolate (PPh 3 )[Ru]-N 3 CS(S) (5), which converts to the isothiocyanate complexes (PPh 3 )[Ru]-NCS (6) and ( t BuNC)[Ru]-NCS (7). Other reagents also react with 2, but the products do not result from [3+2] cycloadditions. Terminal alkynes undergo ligand substitution reactions rather than a [3+2] cycloaddition with 2 in the presence of H 2 O to produce the carbonyl complexes (CO)[Ru]-CH 2 R (8a, R = Ph; 8b, R = 4-CH 3 Ph) through ruthenium vinylidene intermediates. Reaction of 2 with H-CC-CMe 2 OH in MeOH gives the cationic Fischer carbene complex {(PPh 3 )[Ru] C(OMe)-HCC(Me) 2 } + (10). In contrast, reaction of H-CC-CH 2 CH 2 OH gives rise to the five-membered cyclic oxycarbene complex {(PPh 3 )[Ru]C 4 H 6 O} + (11). Several cationic imine complexes {( t BuNC)[Ru]-(NHCHR′)} + (12a, R′ = H; 12b, R′ = CH 3 ; 12c, R′ = Ph) are formed by the reaction of RCH 2 X with 2. If the reaction of 2 with CH 3

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Synthesis and X-ray crystal structures of the cyclic oxacarbene complexes (n = 1 or 2): boat conformation of the 2-oxacyclohexylidene ligand

Cited by 20 publications

References 18 publications

Nucleophilic Addition Reactions to Allenylidene Complexes of Ruthenium Bearing Hemilabile P,N Ligands: Isolation of the Vinylcarbene Complex [Cp*Ru═CHCH═CPh₂(ⁱPr₂PNHPy)][PF₆]

Preparation, Characterization, and Reactivity of Azido Complex Containing a Tp(^tBuNC)(PPh₃)Ru Fragment and Ruthenium-Catalyzed Cycloaddition of Organic Azides with Alkynes in Organic and Aqueous Media

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Synthesis and X-ray crystal structures of the cyclic oxacarbene complexes (n = 1 or 2): boat conformation of the 2-oxacyclohexylidene ligand

Cited by 20 publications

References 18 publications

Nucleophilic Addition Reactions to Allenylidene Complexes of Ruthenium Bearing Hemilabile P,N Ligands: Isolation of the Vinylcarbene Complex [Cp*Ru═CHCH═CPh2(iPr2PNHPy)][PF6]

Preparation, Characterization, and Reactivity of Azido Complex Containing a Tp(tBuNC)(PPh3)Ru Fragment and Ruthenium-Catalyzed Cycloaddition of Organic Azides with Alkynes in Organic and Aqueous Media

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Nucleophilic Addition Reactions to Allenylidene Complexes of Ruthenium Bearing Hemilabile P,N Ligands: Isolation of the Vinylcarbene Complex [Cp*Ru═CHCH═CPh₂(ⁱPr₂PNHPy)][PF₆]

Preparation, Characterization, and Reactivity of Azido Complex Containing a Tp(^tBuNC)(PPh₃)Ru Fragment and Ruthenium-Catalyzed Cycloaddition of Organic Azides with Alkynes in Organic and Aqueous Media