Reactions of Ruthenium Vinylidene and Acetylide Complexes Containing Trichloromethyl Groups: Preparation of a Cyclobutenonyl Complex by Solid‐State Photolysis

Wu, Chung‐Yeh; Chou, Hsien-Hsin; Lin, Ying-Chih; Wang, Yu; Liu, Yi-Hung

doi:10.1002/chem.200802133

Cited by 10 publications

(2 citation statements)

References 110 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several mechanisms for the coupling reaction of alkynes with alkenes have been proposed under homogeneous catalysis conditions. The first is a pathway via the formation of a ruthenacycle intermediate (Scheme , path A)11a,f and the second involves the generation of Ru hydride species, followed by the successive insertion of alkyne and alkene to RuH or RuC bonds (path B) 11e,22,23. Although a mechanism that includes the activation of an sp 2 CH bond of acrylate has also been proposed,11g,12c the absence of the formation of a cis isomer at the α,β position of dienes and no isomerization in the course of the reaction suggest that the pathway via sp 2 CH bond activation seems to be unlikely in the present case.…”

Section: Resultsmentioning

confidence: 99%

Intermolecular Coupling of Alkynes with Acrylates by Recyclable Oxide‐Supported Ruthenium Catalysts: Formation of Distorted Ruthenium(IV)‐oxo Species on Ceria as a Key Precursor of Active Species

Miura¹,

Shimura²,

Hosokawa³

et al. 2011

Adv Synth Catal

View full text Add to dashboard Cite

A solid ceria-supported ruthenium catalyst (Ru/CeO 2 ) as well as a zirconia-supported ruthenium catalyst (Ru/ZrO 2 ) showed high activities toward the intermolecular coupling of alkynes with acrylates to give the corresponding 1,3-dienes in high yields. The reaction proceeded in the presence of sodium formate and both internal or terminal alkynes and norbornene could be applied for the catalytic systems. The solid ruthenium catalyst could be recycled for several times without significant loss of activity. The FT-IR and X-ray absorption fine structure (XAFS) studies of ceria-supported ruthenium catalysts showed that a distorted ruthenium(IV)-oxo species on ceria was transformed during the initial stage of the reaction into a low-valent ruthenium species that was effective for the coupling reactions.

show abstract

Section: Resultsmentioning

confidence: 99%

Intermolecular Coupling of Alkynes with Acrylates by Recyclable Oxide‐Supported Ruthenium Catalysts: Formation of Distorted Ruthenium(IV)‐oxo Species on Ceria as a Key Precursor of Active Species

Miura¹,

Shimura²,

Hosokawa³

et al. 2011

Adv Synth Catal

View full text Add to dashboard Cite

show abstract

“…In the reactions of various propargylic alcohols with [Ru]Cl, γ‐hydroxyvinylidene,5c, 8a vinylvinylidene,8b–c allenylidene,8d or phosphonium acetylide9e complexes were possible products. However, here, the allenylidene complex 2a is isolated as the only product and the γ‐hydroxyvinylidene species A is proposed as the intermediate.…”

Section: Resultsmentioning

confidence: 99%

Reactions of Ruthenium–Allenylidene Complexes Tethering a Cyclopropyl Group

Chen

Cheng

Huang

et al. 2011

Chemistry An Asian Journal

Self Cite

View full text Add to dashboard Cite

Two cyclopropyl allenylidene complexes [Ru]=C=C=C(R)(C(3)H(5)) ([Ru]=[RuCp(PPh(3))(2)], Cp=Cyclopentadienyl; R=thiophene (2a) and R=Ph (2b)) are prepared from the reactions of [Ru]Cl with the corresponding 1-cyclopropyl-2-propyn-1-ol in the presence of KPF(6). Thermal treatment, halide-anion addition, and palladium-catalyzed reactions of 2a and 2b all lead to a ring expansion of the cyclopropyl group, giving the vinylidene complexes 4a and 4b, respectively, each with a five-membered ring. This ring expansion proceeds by C-C bond formation between Cβ of the cumulative double bond and a methylene group of the cyclopropyl ring. In the reaction of 2a with pyrrole, consecutive formation of two C-C bonds, one between C-2 of pyrrole and Cγ of 2a and the other between C-3 of pyrrole and Cα, results in the formation of 6a. The reaction proceeds by addition of pyrrole and 1,3-proton shifts. The hydrogenation of 2a by NaBH(4) is carried out in different solvents. The cumulative double bonds are reduced regioselectively to give a mixture of 7a and 8a. Interestingly, use of different solvents leads to different ratios of 7a and 8a. Presence of a protic solvent like methanol in dichloromethane or chloroform solution increases the yield of 8a, thus revealing that both the rates of hydroboration and deboronation increase. The structures of two new complexes 4a and 6a have been firmly established by X-ray diffraction analysis.

show abstract

Reactions of a Ruthenium Complex with Substituted N‐Propargyl Pyrroles

Chia

Huang

Liu

et al. 2016

Chemistry An Asian Journal

Self Cite

View full text Add to dashboard Cite

In an investigation into the chemical reactions of N-propargyl pyrroles 1 a-c, containing aldehyde, keto, and ester groups on the pyrrole ring, with [Ru]-Cl ([Ru]=Cp(PPh3 )2 Ru; Cp=C5 H5 ), an aldehyde group in the pyrrole ring is found to play a crucial role in stimulating the cyclization reaction. The reaction of 1 a, containing an aldehyde group, with [Ru]-Cl in the presence of NH4 PF6 yields the vinylidene complex 2 a, which further reacts with allyl amine to give the carbene complex 6 a with a pyrrolizine group. However, if 1 a is first reacted with allyl amine to yield the iminenyne 8 a, then the reaction of 8 a with [Ru]-Cl in the presence of NH4 PF6 yields the ruthenium complex 9 a, containing a cationic pyrrolopyrazinium group, which has been fully characterized by XRD analysis. These results can be adequately explained by coordination of the triple bond of the propargyl group to the ruthenium metal center first, followed by two processes, that is, formation of a vinylidene intermediate or direct nucleophilic attack. Additionally, the deprotonation of 2 a by R4 NOH yields the neutral acetylide complex 3 a. In the presence of NH4 PF6 , the attempted alkylation of 3 a resulted in the formation the Fischer-type amino-carbene complex 5 a as a result of the presence of NH3, which served as a nucleophile. With KPF6, the alkylation of 3 a with ethyl and benzyl bromoacetates afforded the disubstituted vinylidene complexes 10 a and 11 a, containing ester groups, which underwent deprotonation reactions to give the furyl complexes 12 a and 13 a, respectively. For 13 a, containing an O-benzyl group, subsequent 1,3-migration of the benzyl group was observed to yield product 14 a with a lactone unit. Similar reactivity was not observed for the corresponding N-propargyl pyrroles 1 b and 1 c, which contained keto and ester groups, respectively, on the pyrrole ring.

show abstract

Reactions of Ruthenium Vinylidene and Acetylide Complexes Containing Trichloromethyl Groups: Preparation of a Cyclobutenonyl Complex by Solid‐State Photolysis

Cited by 10 publications

References 110 publications

Intermolecular Coupling of Alkynes with Acrylates by Recyclable Oxide‐Supported Ruthenium Catalysts: Formation of Distorted Ruthenium(IV)‐oxo Species on Ceria as a Key Precursor of Active Species

Intermolecular Coupling of Alkynes with Acrylates by Recyclable Oxide‐Supported Ruthenium Catalysts: Formation of Distorted Ruthenium(IV)‐oxo Species on Ceria as a Key Precursor of Active Species

Reactions of Ruthenium–Allenylidene Complexes Tethering a Cyclopropyl Group

Reactions of a Ruthenium Complex with Substituted N‐Propargyl Pyrroles

Contact Info

Product

Resources

About