137591-57-2Relevant academic research and scientific papers
Selective one-pot access to symmetrical or unsymmetrical diaryl ethers by copper-catalyzed double arylation of a simple oxygen source
Tlili, Anis,Monnier, Florian,Taillefer, Marc
supporting information; experimental part, p. 12299 - 12302 (2011/02/16)
Great CO-mbination: A novel method is reported for the controlled one-pot synthesis of various symmetrical or unsymmetrical diaryl ethers by double arylation of a simple inorganic oxygen source (see scheme). This versatile and highly selective process is based on the use of a cheap and low toxicity copper catalytic system.
Combining Homogeneous Catalysis with Heterogeneous Separation using Tunable Solvent Systems
Blasucci, Vittoria M.,Husain, Zainul A.,Fadhel, Ali Z.,Donaldson, Megan E.,Vyhmeister, Eduardo,Pollet, Pamela,Liotta, Charles L.,Eckert, Charles A.
experimental part, p. 3932 - 3938 (2010/08/04)
Tunable solvent systems couple homogeneous catalytic reactions to heterogeneous separations, thereby combining multiple unit operations into a single step and subsequently reducing waste generation and improving process economics. In addition, tunable solvents can require less energy than traditional separations, such as distillation. We extend the impact of such solvents by reporting on the application of two previously described carbon dioxide tunable solvent systems: polyethylene glycol (PEG)/organic tunable solvents (POTS) and organic/aqueous tunable solvents (OATS). In particular, we studied: (1) the palladium catalyzed carbon-oxygen coupling of 1-bromo-3,5-dimethylbenzene and o-cresol to potassium hydroxide to produce o-tolyl-3,5-xylyl ether and 1-bromo-3,5-di-tert-butylbenzene to potassium hydroxide to produce 3,5-di-tert-butylphenol in PEG400/1,4-dioxane/water and (2) the rhodium-catalyzed hydroformylation of p-methylstyrene in water/ acetonitrile to form 2-(p-tolyl) propanal. In addition, we introduce a novel tunable solvent system based on a modified OATS where propane replaces carbon dioxide. This represents the first use of propane in a tunable solvent system.
Aminoarenethiolato-copper(I) as (pre-)catalyst for the synthesis of diaryl ethers from aryl bromides and sequential C-O/C-S and C-N/C-S cross coupling reactions
Sperotto, Elena,Van Klink, Gerard P.M.,De Vries, Johannes G.,Van Koten, Gerard
experimental part, p. 9009 - 9020 (2011/01/04)
A small library of 2-aminoarenethiolato-copper(I) (CuSAr) complexes was tested as (pre-)catalysts in the arylation reaction of phenols with aryl bromides. These copper(I) (pre-)catalysts are thermally stable, soluble in common organic solvents, and allow reactions of 6 h at 160 °C with low catalyst loadings of 2.5 mol %. Among the (pre-)catalysts screened, 2-[(dimethylamino)methyl]benzenethiolato-copper(I) (1c) led to the best results and provided good to excellent yields of various substituted diaryl ethers. Mechanistic studies showed that at early stages of the C-O coupling reaction the CuSAr complex is converted into CuBr(PhSAr) via selective coupling of the monoanionic arenethiolato ligand with phenyl bromide with formation of CuBr. In addition, the first results are shown involving a multi-component reaction (MCR) protocol for the in situ synthesis of propargylamines and their subsequent conversion involving a C-O cross coupling reaction. Furthermore, two examples of sequential C-O/C-S and C-N/C-S cross coupling reactions have been carried out on the same dihalo-pyridine substrate in a one-pot process with the same (CuSAr) (pre-)catalyst (overall yields 40-80%).
Use of tunable ligands allows for intermolecular Pd-catalyzed C-O bond formation
Vorogushin, Andrei V.,Huang, Xiaohua,Buchwald, Stephen L.
, p. 8146 - 8149 (2007/10/03)
Bulky biaryl phosphine ligands facilitate Pd-catalyzed C-O coupling reactions of aryl halides with primary and secondary alcohols by promoting reductive elimination at the expense of β-hydride elimination. The key to their success is the ability to match the size of the ligand to that of the combination of substrates. The efficient coupling of a number of unactivated aryl chlorides and bromides with cyclic and acyclic secondary alcohols was achieved. This included the coupling of allylic alcohols for the first time in a Pd-catalyzed coupling process.
