39720-45-1Relevant academic research and scientific papers
Synthesis of tailored perfluoro unsaturated monomers for potential applications in proton exchange membrane preparation
Casiello, Michele,Cotugno, Pietro,Fracassi, Francesco,Milella, Antonella,Monopoli, Antonio,Nacci, Angelo,Palumbo, Fabio
supporting information, (2021/09/24)
The aim of the present work is the synthesis and characterization of new perfluorinated monomers bearing, similarly to Nafion, acidic groups for proton transport for potential and future applications in proton exchange membrane (PEM) fuel cells. To this e
Pd-catalyzed sequential C-C bond formation and cleavage: Evidence for an unexpected generation of arylpalladium(II) species
Youn, So Won,Kim, Byung Seok,Jagdale, Arun R.
supporting information; experimental part, p. 11308 - 11311 (2012/08/28)
A Pd(II)-catalyzed reaction engaging alkenyl β-keto esters is reported that leads to the formation of 1-naphthols and an unexpected generation of arylpalladium(II) species. Interception of the in situ generated arylpalladium(II) species in a Mizoroki-Heck reaction, together with additional mechanistic studies, provided strong evidence in support of the first aromatization-driven β-carbon elimination process. A single Pd catalyst served to promote a series of both C-C bond forming and cleavage events in an unprecedented manner.
Wittig reactions in water media employing stabilized ylides with aldehydes. Synthesis of α,β-unsaturated esters from mixing aldehydes, α-bromoesters, and Ph3P in aqueous NaHCO3
El-Batta, Amer,Jiang, Changchun,Zhao, Wen,Anness, Robert,Cooksy, Andrew L.,Bergdahl, Mikael
, p. 5244 - 5259 (2008/02/07)
(Chemical Equation Presented) Water is demonstrated to be an effective medium for the Wittig reaction over a wide range of stabilized ylides and aldehydes. Despite sometimes poor solubility of the reactants, good chemical yields normally ranging from 80 to 98% and high E-selectivities (up to 99%) are achieved, and the rate of the reactions in water is unexpectedly accelerated. The efficiency of water as a medium in the Wittig reaction is compared to conventional organic solvents ranging from carbon tetrachloride to methanol. The aqueous Wittig reaction works best when large hydrophobic entities are present, such as aromatic, heterocyclic aromatic carboxaldehydes, and long-chain aliphatic aldehydes with triphenylphosphoranes. The E/Z-isomeric ratio of the Wittig products appears dependent on the electron-accepting/donating capacity and the location of the substituents present in the aromatic ring. The effect of additives, such as benzoic acid, LiCl, and sodium dodecyl sulfate (SDS), on the Wittig reaction has been explored. The Wittig reaction can also be conducted in the presence of acidic entities, such as phenols and carboxylic acids. In addition, large α-substituents in the aliphatic aldehydes do not jeopardize the reaction. It is also demonstrated that hydrates of aldehydes can be used directly in the aqueous Wittig reaction as substrates. The scope of the aqueous Wittig reaction is extended to 24 examples of one-pot mixtures of Ph3P, α-bromoesters, and aldehydes in sodium bicarbonate solution (at 20°C for 40 min to 3 h) to provide Wittig products of up to 99% yield and up to 98% E-selectivity. Since water is inexpensive, extremely easy to handle, and represents no environmental concerns, it should be considered a possible medium for new organic reactions.
Water is an efficient medium for Wittig reactions employing stabilized ylides and aldehydes
Dambacher, Jesse,Zhao, Wen,El-Batta, Amer,Anness, Robert,Jiang, Changchun,Bergdahl, Mikael
, p. 4473 - 4477 (2007/10/03)
Water is demonstrated to be an excellent medium for the Wittig reaction employing stabilized ylides and aldehydes. Although the solubility in water appears to be an unimportant characteristic in achieving good chemical yields and E/Z-ratios, the rate of W
Palladium-based system for the polymerization of acrylates. Scope and mechanism
Elia, Christine,Elyashiv-Barad, Sharon,Sen, Ayusman,López-Fernández, Raquel,Albéniz, Ana C.,Espinet, Pablo
, p. 4249 - 4256 (2008/10/08)
The neutral palladium complex [Pd(C6F5)Br(NCMe)2] (1) was found to effect the polymerization of acrylates upon addition of 1 equiv of a monodentate phosphine or pyridine or an excess of halide. Methyl methacrylate was not polymerized, and furthermore, its addition stopped the progress of independently initiated methyl acrylate polymerization in the phosphine-based system. Addition of ethene also inhibited the polymerization of methyl acrylate. However, over 10 mol % incorporation of 1-hexene in the polymer was achieved when the latter was added together with methyl acrylate. The polymerizaion mechanism is discussed.
A novel one-pot synthesis of fluorinated α,β-unsaturated esters
Shen,Xiang
, p. 1403 - 1408 (2007/10/02)
The reaction of pentafluorophenylmethylenetriphenylarsorane or p-chloro-tetrafluorophenylmethylenetriphenylarsorane, generated in situ from methylenetriphenylarsorane and hexafluorobenzene or chloropentafluorobenzene, with bromoacetates giving excellent y
