108-90-7Relevant articles and documents
Synergistic Activities in the Ullmann Coupling of Chloroarenes at Ambient Temperature by Pd-Supported Calcined Ferrocenated La2O3
Chumkaeo, Peerapong,Poonsawat, Thinnaphat,Meechai, Titiya,Somsook, Ekasith
, (2019)
Novel palladium-doped nanoparticles have been explored to serve as the first metal oxide-derived heterogeneous catalyst for Ullmann reaction of chloroarenes under mild condition (34?°C). This heterogeneous catalyst exhibited high catalytic activity towards the Ullmann homocoupling of chloroarenes into a series of useful symmetrically biaryl products with good to excellent yields in the presence of ethanol and NaOH, thereby leading to green and economical Ullmann reaction. The produced nanoparticles were successfully characterized by various techniques including PXRD, XPS, HRTEM, SEM-EDS, BET, TGA techniques, elemental mapping analysis and ICP-OES. Interestingly, based on characterization and experimental data, a reasonable mechanism has been proposed. Also, the formation of aryl methyl ketone as a by-product has been further confirmed by isotopic labelling experiments that the acetyl moiety is derived from ethanol. Moreover, the catalyst was stable and could be easily reused up to 5 times under atmospheric air without suffering significant loss in catalytic activity.
Dechlorination of pentachlorophenol and 1,2,4-trichlorobenzene using NaBH4 and NaBH4/LiCl at 125-315°C in glyme solvents
Yang, Cangming,Pittman Jr., Charles U.
, p. 517 - 525 (1998)
Dechlorinations of pentachlorophenol and 1,2,4-trichlorobenzene were achieved using NaBH4 in tetraglyme at 290-315°C and by NaBH4/LiCl at 125-135°C in diglyme, triglyme or tetraglyme after premixing at room temperature.
A Zn4L6 Capsule with Enhanced Catalytic C?C Bond Formation Activity upon C60 Binding
Lu, Zhenpin,Lavendomme, Roy,Burghaus, Olaf,Nitschke, Jonathan R.
, p. 9073 - 9077 (2019)
A redox-switchable self-assembled ZnII4L6 cage was synthesized that contains naphthalenediimide (NDI) motifs. Its reduction lent these NDI panels persistent radical anion character. The redox activity of this cage allows it to act as a catalyst for the oxidative coupling of different tetraaryl borates to give biaryls. The catalytic activity of the cage was enhanced following its binding of C60, which implies a mechanism that does not involve encapsulation of the substrate.
Kinetics and mechanism of the gas phase reaction of Cl atoms and OH radicals with bromobenzene
Nakano,Kawasaki,Ponomarev,Hurley,Wallington
, p. 77 - 83 (2002)
Relative rate techniques were used to study the kinetics and mechanism of the reaction of Cl atoms and OH radicals with bromobenzene (C6H5Br) in 20-700 Torr of N2, O2, or air diluent at 295 ± 2 K. Using the observed rate constant ratios k(C6H5Br+Cl) /k(C2H5Cl+Cl) = 1.56 ± 0.05 and k(C6H5Br+Cl)/k(C2H6+Cl) = 0.24 ± 0.01, the C6H5Br+Cl rate constant is determined to be k(C6H5Br+Cl) = (1.32 ± 0.20) × 10-11 cm3 molecule-1 S-1 giving exclusively C6H5Cl through a displacement mechanism. Using the observed rate constant ratios k(C6H5Br+OH)/ k(C6H6 + OH) = 0.77 ± 0.06 and k(C6H5Br+OH)/k(C2H4+OH) = 0.11 ± 0.004, the C6H5Br + OH rate constant is determined to be k(C6H5Br+OH) = (9.37±2.04) × 10-13 cm3 molecule-1 s-1. The product expected from a displacement mechanism, phenol, was not observed (10% yield).
Alkane oxidation by an immobilized nickel complex catalyst: Structural and reactivity differences induced by surface-ligand density on mesoporous silica
Nakazawa, Jun,Hori, Tomoaki,Stack, T. Daniel P.,Hikichi, Shiro
, p. 1191 - 1199 (2013)
Immobilized nickel catalysts SBA*-L-x/Ni (L=bis(2-pyridylmethyl)(1H- 1,2,3-triazol-4-ylmethyl)amine) with various ligand densities (L content (x)=0.5, 1, 2, 4 mol % Si) have been prepared from azidopropyl-functionalized mesoporous silicas SBA-N3/sub
Kinetic study of the reactions of chlorine atoms and Cl2·- radical anions in aqueous : Solutions. 1. Reaction with benzene
Martire,Bertolotti,Braun,Gonzalez,Alegre,Gerones,Rosso
, p. 3117 - 3125 (2000)
The photolysis of NaS2O8 aqueous solutions containing Cl- ions is a clean technique for kinetic studies of the species Cl./Cl2.- in the presence and absence of added aromatic substrates. Laser and conventional flash-photolysis methods were used to study the aqueous phase reactions of chlorine atoms and Cl2.- (340 nm) radical ions in the presence and absence of benzene. A mechanism that considers the decay of Cl2.- in aqueous solutions with chloride ion concentrations from 1 x 10-4 to 0.6 M, total radical (Cl. + Cl2.-) concentrations at (0.1-1.5) x 10-5 M, and 2.5-3 pH was proposed. Kinetic computer simulations supported interpretation of the experimental data. The rate constants 6 x 109/M-sec ≤ k ≤ 1.2 x 1010/M-sec and 5/M-sec were determined for the reactions of Cl. and Cl2.-, respectively, in the aqueous phase. The organic radicals produced from these reactions showed an absorption band with maximum at 300 nm that was assigned to a Cl-cyclohexadienyl radical (Cl-CHD). The kinetic analysis of the traces supported a reversible reaction between Cl-CHD and O2. A reaction mechanism leading to the formation of chlorobenzene was proposed.
Application of a dioxo-molybdenum(VI) complex anchored on TiO2 for the photochemical oxidative decomposition of 1-chloro-4-ethylbenzene under O2
Bakhtchadjian, Robert,Tsarukyan, Samvel,Barrault, Joel,Martinez, Fernando O.,Tavadyan, Levon,Castellanos, Nelson J.
, p. 897 - 900 (2011)
The catalytic activity of dioxo-molybdenum(VI)- dichloro[4,4'- dicarboxylato-2,2'-bipyridine] covalently anchored through the carboxylate function to the surface of TiO2 has been tested for the oxidative degradation of 1-chloro-4- ethylbenzene in MeCN solution under argon and UV irradiation (λ = 254 nm). After 4-5 h of photochemical reaction, the Mo complex was reoxidized in the presence of O2 in the dark, and then the reaction was continued under argon. The reaction proceeds by the intermediate formation of 40-chloroacetophenone that undergoes further decomposition to chlorobenzene, plus small amounts of oxygen-containing organochlorine compounds, CO2 and H2O. Similar results were obtained for the decomposition of 4'-chloroacetophenone under the same conditions, which also gave chlorobenzene as one of the main products. The ratio of [final product]/ [Mo complex] increases during the decomposition of 1-chloro-4-ethylbenzene (up to 350-400% for 30-35 h of reaction), which provides evidence of a catalytic process. The probable photochemical reactions are discussed. Springer Science+Business Media B.V. 2011.
A ligand-free copper-catalyzed decarboxylative trifluoromethylation of aryliodides with sodium trifluoroacetate using Ag2O as a promoter
Li, Yaming,Chen, Tao,Wang, Huifeng,Zhang, Rong,Jin, Kun,Wang, Xiuna,Duan, Chunying
, p. 1713 - 1716 (2011)
A practical and ligand-free Cu-catalyzed decarboxylative trifluoromethylation of aryl iodides with sodium trifluoroacetate using Ag 2O as a promoter was reported. A variety of trifluoromethyl- substituted aromatics are synthesized in moderate to excellent yields and with wide functional-group tolerance under relatively mild reaction conditions. Georg Thieme Verlag Stuttgart · New York.
Oxychlorination and combustion of propene on fly-ash. Formation of chlorinated benzenes, dibenzodioxines and mono- and dibenzofurans
Jarmohamed, W.,Mulder, P.
, p. 1911 - 1918 (1994)
Heterogenous gas phase reactions of propene on fly ash in the presence of hydrochloric acid and air between 300-580 deg C have been investigated. At mild conditions only the formation of polychlorinated C1, C2 and C3 species takes place. At the high tempe
CONVERSION OF DIARYLIODONIUM SALTS TO ARYL FLUORIDES
Puy, Michael van der
, p. 385 - 392 (1982)
The preparation of aryl fluorides by the reaction of diaryliodonium salts with KF is discussed.Generally, best results were obtained when the salt Ar2I(1+)*X(1-) was heated with KF in the absence of solvent.The counterion, X(1-), must be non-nucleophilic.
