583884-57-5Relevant academic research and scientific papers
A Structurally Characterized Fluoroalkyne
Hall, Lewis M.,Tew, David P.,Pridmore, Natalie E.,Whitwood, Adrian C.,Lynam, Jason M.,Slattery, John M.
, p. 7551 - 7556 (2017)
The facile synthesis of a stable and isolable compound with a fluoroalkynyl group, M?C≡CF, is reported. Reaction of [Ru(C≡CH)(η5-C5Me5)(dppe)] with an electrophilic fluorinating agent (NFSI) results in the formation of the
Facile decarboxylation of propiolic acid on a ruthenium center and related chemistry
Bowie, John H.,Bruce, Michael I.,Buntine, Mark A.,Gentleman, Alexander S.,Graham, David C.,Low, Paul J.,Metha, Gregory F.,Mitchell, Cassandra,Parker, Christian R.,Skelton, Brian W.,White, Allan H.
, p. 5262 - 5273 (2012/11/07)
Spontaneous decarboxylation of RC≡CCO2H (R = H, Ph) occurs in reactions with RuCl(PP)Cp (PP = (PPh3)2, dppe) to give [Ru(=C=CHR)(PP)Cp]+. Computational studies (DFT) of possible decarboxylation mechanisms suggest that the reaction that leads to extrusion of CO2 and formation of [Ru(=C=CH2)(dppe)Cp]+ most likely occurs by initial interaction of the anion HC≡CCO2 - with RuCl(dppe)Cp by coordination of carboxylate to Ru, followed by formation of an η2-alkyne intermediate which rearranges to the η1-ethynyl species with loss of CO2. Protonation of the ethynyl group affords the parent vinylidene. In contrast, reactions of HC≡CCO2R (R = Me, Et) with RuCl(PP)Cp and [NH 4]PF6 in MeOH have given [Ru{=C(OMe)CH2(CO 2R)}(PP)Cp]+, formed by attack of MeOH at C α of the intermediate vinylidenes [Ru{=C=CH(CO 2R)}(PP)Cp]+. Deprotonation of the carbenes affords Ru{C(OMe)=CH(CO2R)}(PP)Cp as mixtures of cis and trans isomers. The vinylidenes, which are obtained directly from RuCl(PP)Cp and HC≡CCO 2R in the presence of [NH4]PF6 in Bu tOH, can be deprotonated (Na/PriOH) to the corresponding alkynyls. Attempted deprotonation of [Ru(=C=CH2)(dppe)Cp]+ with LiBu gave the binuclear cyclobutenylidinium complex [{Ru(dppe)Cp} 2(μ-C4H3)]+. The X-ray diffraction molecular structures of [{Ru(dppe)Cp}2(μ-C 4H3)]PF6 (11), [Ru{=C(OMe)CH 2(CO2Me)}(dppe)Cp]PF6 (13), Ru{C(OMe)=CH(CO2R)}(dppe)Cp (R = Me (15), Et (16)) and Ru(C≡CCO2R)(dppe)Cp (R = Me (21), Et (22)) are described.
Substitution of tetracyanoethene by ethynyl-metal complexes gives tricyanovinylethynyl (tricyanobutenynyl) derivatives: Syntheses, protonation, and addition of metal-ligand fragments
Bruce, Michael I.,Fox, Mark A.,Low, Paul J.,Nicholson, Brian K.,Parker, Christian R.,Patalinghug, Wyona C.,Skelton, Brian W.,White, Allan H.
, p. 2639 - 2657 (2012/06/04)
A series of complexes containing the new tricyanovinylethynyl (3,4,4-tricyanobut-3-en-1-ynyl) ligand have been obtained by substitution of a CN group in tetracyanoethene upon reaction with the ethynyl complexes M(C≡CH)(PP)Cp′ (M = Ru, Os, (PP)Cp′ = (PPh3) 2Cp; M = Ru, PP = dppe, Cp′ = Cp, Cp*). The reactions proceed in higher yield as the metal environment becomes more sterically hindered, the normal [2 + 2]-cycloaddition/ring-opened product M{C[=C(CN) 2]CH=C(CN)2}(PP)Cp′ also being formed in some cases. The diynyl complex Ru(C≡CC≡CH)(dppe)Cp* reacts with tcne to give only the ring-opened adduct Ru{C≡CC[=C(CN)2]CH=C(CN) 2}(dppe)Cp*. Protonation (HBF4 or HPF6) of Ru{C≡CC(CN)=C(CN)2}(dppe)Cp* afforded the vinylidene cation [Ru{=C=CHC(CN)=C(CN)2}(dppe)Cp*]+. A second transition-metal fragment MLn (MLn = Ru(PPh 3)2Cp, M′(dppe)Cp* (M′ = Ru, Os), RuCl(dppe)2) can be added to the CN group trans to the metal center; electrochemical, spectroscopic, and computational studies indicate that there is little ground-state delocalization between the metal centers. In the case of the tricyanovinylethynyl derivatives, an intense MLCT (or ML-LCT) transition can be identified in the visible region, which is responsible for the intense blue to purple color of these species; the analogous transition in the vinylidene-based complexes is significantly blue-shifted. The X-ray crystallographically determined structures of several of these complexes are reported. The cations [{Cp*(dppe)Ru}{μ-(C/N)≡CC(CN)=C(CN) (≡C/N)}{M(dppe)Cp*}]+ (M = Ru, Os) show some C≡C/C≡N disorder (and associated Ru/Os disorder in the case of the heterometallic example) in the crystals.
