Synthesis and reactivity of neutral vinylidene and σ-alkynyl complexes containing the hemilabile ligand Ph2PCH2CH2OMe

Pavlik, Sonja; Gemel, Christian; Slugovc, Christian; Mereiter, Kurt; Schmid, Roland; Kirchner, Karl

doi:10.1016/s0022-328x(00)00648-3

Cited by 43 publications

(31 citation statements)

References 26 publications

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“…The head-to-head homodimerization of terminal alkynes has been carried out using a variety of catalytic systems including ruthenium half-sandwich complexes, − Grubbs’ catalyst, a thiolate-bridged dimeric ruthenium(III), a ruthenium-P,N system, ruthenium-P 4 and osmium P 4 systems, , ruthenium-P,O and osmium-P,O systems, − a Rh(III) catalyst, and iridium systems (Chart ). , …”

Section: Catalytic Reactions Of Metal-complexed Alkenylidenes: Carbon...mentioning

confidence: 99%

Transition Metal Vinylidene- and Allenylidene-Mediated Catalysis in Organic Synthesis

2019

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With their mechanistic novelty and various modalities of reactivity, transition metal unsaturated carbene (alkenylidene) complexes have emerged as versatile intermediates for new reaction discovery. In particular, the past decade has witnessed remarkable advances in the chemistry of metal vinylidenes and allenylidenes, leading to the evolution of a diverse array of new catalytic transformations that are mechanistically distinct from those developed in the previous two decades. This review aims to provide a survey of the recent achievements in the development of organic reactions that make use of transition metal alkenylidenes as catalytic intermediates and their applications to organic synthesis.

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Section: Catalytic Reactions Of Metal-complexed Alkenylidenes: Carbon...mentioning

confidence: 99%

Transition Metal Vinylidene- and Allenylidene-Mediated Catalysis in Organic Synthesis

2019

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“…Other Ru(II) acetylide complexes have been prepared and studied. [66][67][68][69][70][71][72][73] Solid-State Characterization. and TpRu(CO)(PPh 3 )(CtCPh) (7) have been characterized by single-crystal X-ray diffraction studies.…”

Section: Solid-state X-ray Diffraction Studies Of [Tpru(co)(pph 3 )-(mentioning

confidence: 99%

Octahedral Ru(II) Amido Complexes TpRu(L)(L‘)(NHR) (Tp = Hydridotris(pyrazolyl)borate; L = L‘ = P(OMe)₃ or PMe₃ or L = CO and L‘ = PPh₃; R = H, Ph, or ^tBu): Synthesis, Characterization, and Reactions with Weakly Acidic C−H Bonds

et al. 2003

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The octahedral Ru(II) amine complexes [TpRu(L)(L')(NH(2)R)][OTf] (L = L' = PMe(3), P(OMe)(3) or L = CO and L' = PPh(3); R = H or (t)Bu) have been synthesized and characterized. Deprotonation of the amine complexes [TpRu(L)(L')(NH(3))][OTf] or [TpRu(PMe(3))(2)(NH(2)(t)Bu)][OTf] yields the Ru(II) amido complexes TpRu(L)(L')(NH(2)) and TpRu(PMe(3))(2)(NH(t)Bu). Reactions of the parent amido complexes or TpRu(PMe(3))(2)(NH(t)Bu) with phenylacetylene at room temperature result in immediate deprotonation to form ruthenium-amine/phenylacetylide ion pairs, and heating a benzene solution of the [TpRu(PMe(3))(2)(NH(2)(t)Bu)][PhC(2)] ion pair results in the formation of the Ru(II) phenylacetylide complex TpRu(PMe(3))(2)(C[triple bond]CPh) in >90% yield. The observation that [TpRu(PMe(3))(2)(NH(2)(t)Bu)][PhC(2)] converts to the Ru(II) acetylide with good yield while heating the ion pairs [TpRu(L)(L')(NH(3))][PhC(2)] yields multiple products is attributed to reluctant dissociation of ammonia compared with the (t)butylamine ligand (i.e., different rates for acetylide/amine exchange). These results are consistent with ligand exchange reactions of Ru(II) amine complexes [TpRu(PMe(3))(2)(NH(2)R)][OTf] (R = H or (t)Bu) with acetonitrile. The previously reported phenyl amido complexes TpRuL(2)(NHPh) [L = PMe(3) or P(OMe)(3)] react with 10 equiv of phenylacetylene at elevated temperature to produce Ru(II) acetylide complexes TpRuL(2)(C[triple bond]CPh) in quantitative yields. Kinetic studies indicate that the reaction of TpRu(PMe(3))(2)(NHPh) with phenylacetylene occurs via a pathway that involves TpRu(PMe(3))(2)(OTf) or [TpRu(PMe(3))(2)(NH(2)Ph)][OTf] as catalyst. Reactions of 1,4-cyclohexadiene with the Ru(II) amido complexes TpRu(L)(L')(NH(2)) (L = L' = PMe(3) or L = CO and L' = PPh(3)) or TpRu(PMe(3))(2)(NH(t)Bu) at elevated temperatures result in the formation of benzene and Ru hydride complexes. TpRu(PMe(3))(2)(H), [Tp(PMe(3))(2)Ru[double bond]C[double bond]C(H)Ph][OTf], [Tp(PMe(3))(2)Ru=C(CH(2)Ph)[N(H)Ph]][OTf], and [TpRu(PMe(3))(3)][OTf] have been independently prepared and characterized. Results from solid-state X-ray diffraction studies of the complexes [TpRu(CO)(PPh(3))(NH(3))][OTf], [TpRu(PMe(3))(2)(NH(3))][OTf], and TpRu(CO)(PPh(3))(C[triple bond]CPh) are reported.

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“…All other angles between cis-disposed ligands are in the 85.0Ϫ93.8°range, while mutually trans-disposed ligands make angles of approximately 171°at the metal atom. (10) 2.032(7) P(2)ϪRuϪP(1) 99.23(6) P(1)ϪC (6) 1.835(6) P(1)ϪRuϪCl 93.83(6) P(1)ϪC (11) 1.850(7) P(2)ϪRuϪCl 93.28(6) P(2)ϪC (1) 1.807(6) P(2)ϪC (31) 1.823(6) P(2)ϪC (41) 1.862(6) [13,18,19] the nitrogen atom trans to the chloride ligand is closer to the metal center than those opposite to the π-accepting phosphane ligands. Both the cyclopentadienyl (Cp) rings of the dppf ligand are essentially planar, and the phosphorus atoms are situated in the plane of the ring to which they are attached.…”

Section: Synthesis Molecular Structures and Spectroscopic Propertiesmentioning

confidence: 99%

(Allenylidene)ruthenium Complexes with Redox‐Active Substituents and Ligands

et al. 2003

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, L 2 = 2 PPh 3 or 1,1Ј-bis(diphenylphosphanyl)ferrocene (dppf), R = Ph or ferrocenyl] and their spectroscopic and electrochemical characteristics. Three of these compounds possess redox-active, ferrocenebased substituents or ligands − that are oxidized at lower potentials than the ruthenium center itself − attached either to the terminal carbon atom of the allenylidene ligand or to the ruthenium atom. The Fc/Ph-substituted complexes 3a and 3b provide unique examples of hindered rotation of the allenylidene substituent around the M=C bond. For 3a (L 2 = 2 PPh 3 ), two isomers differing in the orientation of the vertically aligned, unsymmetrically substituted allenylidene ligand are discernible even at 388 K. The dppf-substituted congener 3b has the allenylidene ligand in a horizontal orientation and exhibits a rotational barrier, as determined by dynamic 31 P NMR spectroscopy, of ∆G ϶ = 47 kJ/mol at T C = 238 K. The changes in the spectroscopic and electrochemical properties upon replacement of the PPh 3 by a dppf ligand and the Ph by an Fc moiety can be explained in terms of the bonding within these systems. These effects are attenuated when the ferrocene-based redox tags are oxidized, as shown by IR and

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Synthesis and reactivity of neutral vinylidene and σ-alkynyl complexes containing the hemilabile ligand Ph2PCH2CH2OMe

Cited by 43 publications

References 26 publications

Transition Metal Vinylidene- and Allenylidene-Mediated Catalysis in Organic Synthesis

Transition Metal Vinylidene- and Allenylidene-Mediated Catalysis in Organic Synthesis

Octahedral Ru(II) Amido Complexes TpRu(L)(L‘)(NHR) (Tp = Hydridotris(pyrazolyl)borate; L = L‘ = P(OMe)₃ or PMe₃ or L = CO and L‘ = PPh₃; R = H, Ph, or ^tBu): Synthesis, Characterization, and Reactions with Weakly Acidic C−H Bonds

(Allenylidene)ruthenium Complexes with Redox‐Active Substituents and Ligands

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Synthesis and reactivity of neutral vinylidene and σ-alkynyl complexes containing the hemilabile ligand Ph2PCH2CH2OMe

Cited by 43 publications

References 26 publications

Transition Metal Vinylidene- and Allenylidene-Mediated Catalysis in Organic Synthesis

Transition Metal Vinylidene- and Allenylidene-Mediated Catalysis in Organic Synthesis

Octahedral Ru(II) Amido Complexes TpRu(L)(L‘)(NHR) (Tp = Hydridotris(pyrazolyl)borate; L = L‘ = P(OMe)3 or PMe3 or L = CO and L‘ = PPh3; R = H, Ph, or tBu): Synthesis, Characterization, and Reactions with Weakly Acidic C−H Bonds

(Allenylidene)ruthenium Complexes with Redox‐Active Substituents and Ligands

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Product

Resources

About

Octahedral Ru(II) Amido Complexes TpRu(L)(L‘)(NHR) (Tp = Hydridotris(pyrazolyl)borate; L = L‘ = P(OMe)₃ or PMe₃ or L = CO and L‘ = PPh₃; R = H, Ph, or ^tBu): Synthesis, Characterization, and Reactions with Weakly Acidic C−H Bonds