103-36-6Relevant articles and documents
Vinylalumination of fluoro-carbonyl compounds
Ramachandran, P. Veeraraghavan,Reddy, M. Venkat Ram,Rudd, Michael T.,De Alaniz, Javier Read
, p. 8791 - 8794 (1998)
Ethyl acrylate and acrylonitrile fail to undergo efficient Baylis- Hillman reaction with fluoral, but provide good yields of products with pentafluorobenzaldehyde. Alternately, unsubstituted and β-substituted [α- (ethoxycarbonyl)vinyl]aluminum react with perfluoroalkyl and -aryl aldehydes and ketones to provide the α-hydroxyalkenylated fluoro-organic compounds in good to excellent yields.
Unusual temperature dependence of salt effects for "on water" Wittig reaction: Hydrophobicity at the interface
Tiwari, Shraeddha,Kumar, Anil
, p. 4445 - 4447 (2008)
An unusual variation with temperature of the salt effects in aqueous Wittig reaction is observed, suggesting that hydrophobic acceleration of reactions comprising "on water" reactants is fundamentally different from that for reactions with small non-polar solutes. The Royal Society of Chemistry.
Pd/Cu-Free Cobalt-Catalyzed Suzuki and Heck Using Green Bio-Magnetic Hybrid and DFT-Based Theoretical Study
Hajipour, Abdol R.,Khorsandi, Zahra,Ahmadi, Mehnoosh,Jouypazadeh, Hamidreza,Mohammadi, Bahareh,Farrokhpour, Hossein
, p. 2842 - 2850 (2021)
Abstract: Several highly efficient and magnetically recyclable cobalt catalytic systems were prepared using magnetic chitosan and some safe and available organic compounds (Co-ligand@MNPs/Ch). The structure of these nanocomposites was confirmed by various physicochemical techniques such as FT-IR, XRD, TGA, VSM, TEM, SEM, CHNS and ICP-OES. These nano composites exhibit remarkable catalytic efficiency for Suzuki and Heck cross-coupling reactions in mild and green reaction conditions. The facile accessibility of starting materials, possible performance in air and eco-friendly conditions are merits of our catalysts. In addition, to describe and go insight to role and effect of ligands present in these catalysts, electrostatic interactions, density functional theory (DFT) model in molecular method were employed. Graphic Abstract: [Figure not available: see fulltext.]
Meta -Selective C-H functionalisation of aryl boronic acids directed by a MIDA-derived boronate ester
Cordier, Christopher J.,Spivey, Alan C.,White, Andrew J. P.,Williams, Alexander F.
, p. 3301 - 3306 (2020)
N-Methyliminodiacetic acid (MIDA) boronates are boronic acid derivatives which are stable to reduction, oxidation and transmetalation. This has led to their widespread use as boronic acid protecting groups (PGs) and in iterative cross-couplings. We describe herein the development of a novel MIDA derivative that acts in a dual manner, as a protecting group and a directing group (DG) for meta C(sp2)-H functionalisation of arylboronic acids. Palladium catalysed C-H alkenylations, acetoxylations and arylations are possible, at room temperature and under aerobic conditions. Deprotection to reveal the functionalised boronic acids is rapid and allows for full recovery of the DG. The technique allows the facile diversification of aryl boronic acids and their subsequent use in a range of reactions or in iterative processes.
Magnetically recoverable nanostructured Pd complex of dendrimeric type ligand on the MCM-41: Preparation, characterization and catalytic activity in the Heck reaction
Abdollahi-Alibeik, Mohammad,Gharibpour, Najmeh,Ramazani, Zahra
, p. 184 - 199 (2020)
A palladium complex of a dendrimer type ligand of aminoethylacrylamide immobilized onto the mesoporous channels of MCM-41 with magnetic core was prepared and characterized using various techniques such as XRD, TEM, BET, FT-IR, TGA, and VSM. The prepared nanostructured material was found as a magnetically recoverable catalyst for Heck reaction of aryl halides and vinylic C-H. The catalyst is easily recoverable with an external magnet and is reusable with different leaching amounts depending to loading of Pd. A hot filtration test was also performed and gave evidence that Palladium in heterogeneous samples can dissolve and then redeposit on the surface of the support material.
Palladium(II) oxide impregnated on magnetite as a catalyst for the synthesis of 4-arylcoumarins: Via a Heck-arylation/cyclization process
Pérez, Juana M.,Cano, Rafael,McGlacken, Gerard P.,Ramón, Diego J.
, p. 36932 - 36941 (2016)
Heck-arylation/cyclization was achieved using heterogeneous palladium(ii) oxide impregnated on magnetite catalyst (2.5 mol%) with a lower catalyst loading than that reported for similar processes. Ethanol was used as a non-toxic and bio-renewable solvent. Good yields were afforded using a broad range of substrates (40-98%). The catalyst could be partially recycled, and analyses confirmed the almost total reduction of palladium(ii) oxide to palladium(0) as well as the iodine poissoning effect, which is the main barrier to complete recyclability.
Mesoporous Borated Zirconia: A Solid Acid-Base Bifunctional Catalyst
Sinhamahapatra, Apurba,Pal, Provas,Tarafdar, Abhijit,Bajaj, Hari C.,Panda, Asit Baran
, p. 331 - 338 (2013)
The development and use of reusable solid catalysts for the selective organic transformation in solvent-free or environmentally benign solvent media is the key interest of modern frontier science. Herein a facile low temperature aqueous solution based chemical route for the synthesis of mesoporous borated zirconia, an acid-base bifunctional solid catalyst, using aqueous zirconium ammonium carbonate complex and borax in presence of cetyltrimethylammonium bromide is presented. The material has a very high surface area and acidity with weak basicity. The catalytic activity of the material was investigated for the solvent-free Knoevenagel condensation reaction of benzaldehyde/substituted benzaldehyde and malononitrile/cyano ethylacetate to confirm the acid-base bifunctionality. High yield (>90%) of the corresponding benzylidene was obtained within 15-30min at room temperature. The evidence that the high catalytic activity is a result of acid-base bifunctionality of the synthesized borated zirconia material was further supported by performing Claisen-Schmidt condensation of benzaldehyde and acetophenone. The methodology was also extended for targeted synthesis of cinnamyl ethyl ester and coumarin or coumarin ester; and resulted in a good yield.
A sequential tetra-n-propylammonium perruthenate (TPAP)-Wittig oxidation olefination protocol
MacCoss, Rachel N.,Balskus, Emily P.,Ley, Steven V.
, p. 7779 - 7781 (2003)
A convenient sequential oxidation-olefination protocol is reported using tetra-n-propylammonium perruthenate (TPAP) as oxidant and phosphonium salts as olefin source. The oxidation reaction mixture is added directly to the phosphorane facilitating an efficient method for this transformation that avoids work-up of potentially sensitive aldehyde intermediates.
Controlling reactivity in the Fujiwara–Moritani reaction: Examining solvent effects and the addition of 1,3-dicarbonyl ligands on the oxidative coupling of electron rich arenes and acrylates
Jones, Roderick C.
, (2020)
A palladium-catalysed direct alkenation of electron rich arenes in the presence of K2S2O8 with an acetic acid/1,4-dioxane solvent combination has been developed. The 1,4-dioxane co-solvent dramatically influences the rate of reaction, giving selectively disubstituted alkenes, while the addition of acetylacetone ligands was shown to increase site selectivity for the alkenation of monofunctionalized arenes. The participation of these carbonyl ligands has been confirmed by ESI-MS studies, with some key in situ intermediates in the catalytic cycle identified. A variety of electron rich arenes and olefinic substrates can be utilised in the direct oxidative coupling to give disubstituted alkenes in moderate to good yields.
A photoredox catalysed Heck reaction: Via hole transfer from a Ru(ii)-bis(terpyridine) complex to graphene oxide
Rosenthal, Marta,Lindner, J?rg K. N.,Gerstmann, Uwe,Meier, Armin,Schmidt, W. Gero,Wilhelm, René
, p. 42930 - 42937 (2020)
The attachment of homoleptic Ru bis-terpy complexes on graphene oxide significantly improved the photocatalytic activity of the complexes. These straightforward complexes were applied as photocatalysts in a Heck reaction. Due to covalent functionalization on graphene oxide, which functions as an electron reservoir, excellent yields were obtained. DFT investigations of the charge redistribution revealed efficient hole transfer from the excited Ru unit towards the graphene oxide. This journal is
