4341-02-0Relevant articles and documents
Cu-Catalyzed Denitrogenative Transannulation of 3-Aminoindazoles to Assemble 1-Aminoisoquinolines and 3-Aminobenzothiophenes
Zhou, Yao,Wang, Ya,Lou, Yixian,Song, Qiuling
, p. 8869 - 8873 (2019/09/12)
We disclose a novel Cu-catalyzed denitrogenative transannulation of 3-aminoindazoles to afford diverse functionalized 3-aminobenzothiophenes and 1-aminoisoquinolines, in which denitrogenative transannulation of 3-aminoindazoles is reported for the first t
Palladium-mediated radical homocoupling reactions: A surface catalytic insight
Favier, Isabelle,Toro, Marie-Lou,Lecante, Pierre,Pla, Daniel,Gómez, Montserrat
, p. 4766 - 4773 (2018/09/29)
In this contribution, we report a palladium nanoparticle-promoted reductive homocoupling of haloarenes that proceeds efficiently to produce corresponding bis-aryls in moderate to excellent yields using relatively low catalyst loading (1 mol%), and exhibits broad functional group tolerance. This work sheds light on how the surface state of Pd(0) nanoparticles plays a crucial role in the reactivity of catalytic systems. Notably, the appropriate choice of palladium salts for the preparation of the preformed nanocatalysts was a key parameter having a major impact on the catalytic activity; thus, the effect of halide anions on the reactivity of the as-prepared palladium nanoparticles could be assessed, with iodide anions being capable of inhibiting the corresponding homocoupling reaction. The homocoupling reaction mechanism has been further studied by means of radical trap and electron paramagnetic resonance (EPR) experiments, revealing that the reaction proceeds via radical intermediates. Taking into account these data, a plausible reaction mechanism based on single-electron transfer processes on the palladium nanoparticle surface is discussed.
An efficient preparation for 2-Cyano-4'-methylbiphenyl in toluene-tetrahydrofuran solvents over transition-metal catalysts
Qian, Haixia,Peng, Xinhua,Wu, Xiangrui
experimental part, p. 6341 - 6344 (2011/01/12)
2-Cyano-4'-methyl-biphenyl, which is a key intermediate used for the preparation of anti-hypertensive drugs, was easily synthesized by the coupling of non-active o-chlorobenzonitrile with p-chlorotoluene in toluene-tetrahydrofuran mixed solvents over transition-metal catalysts. Various reaction conditions, especially catalysis of some catalysts were discussed to improve selectivity suitable for industrialization in the recycle solvent system.
Efficient cobalt-catalyzed formation of unsymmetrical biaryl compounds and its application in the synthesis of a sartan intermediate
Amatore, Muriel,Gosmini, Corinne
supporting information; experimental part, p. 2089 - 2092 (2009/02/06)
(Chemical Equation Presented) No prior preparation of the organometallic reagent is required in a cobalt-catalyzed coupling of two different aryl halides under mild conditions (see scheme). A broad spectrum of valuable biaryl compounds can be prepared in this way. Not only may a variety of reactive substituents be present, but heteroaryl halides and aryl triflates are also suitable substrates. DMF = N,N-dimethylformamide, FG = functional group.
Gas-phase thermolysis of condensed-1,2,4-triazines: interesting routes toward heterocyclic ring systems
Al-Awadi, Hanan,Ibrahim, Maher R.,Al-Awadi, Nouria A.,Ibrahim, Yehia A.
, p. 12948 - 12953 (2008/03/28)
Gas-phase thermolysis of thieno[2,3-e][1,2,4]triazines gave benzonitrile, isothiazole, pyridazine, and thieno[2,3-d]thiazole derivatives. Similar transformation of benzo[1,2,4]triazine and phenanthro[9,10-e][1,2,4]triazine derivatives into their corresponding condensed thiazoles has been achieved by heating at 350 °C with sulfur. A mechanism for these pyrolytic transformations was proposed.
An efficient phosphine-free palladium coupling for the synthesis of new 2-arylbenzo[b]thiophenes
Dit Chabert, Jérémie Fournier,Joucla, Lionel,David, Emilie,Lemaire, Marc
, p. 3221 - 3230 (2007/10/03)
Straightforward and rapid access to 2-arylbenzo[b]thiophenes has been developed. It involved a catalytic coupling of 3-activated benzo[b]thiophenes with several aryl halides in the presence of a phosphine-free palladium system. In case of fragile functional groups such as aldehydes, a quaternary ammonium was used as an additive as with the other substrates, the coupling performed better and faster in the presence of a crown ether, the best one being DCH-18-C-6, with good yields and low reaction times. This method would provide a direct access to novel structures of biological interest.
Process of heterocoupling by electrolytic microbattery, use of cobalt for implementing said coupling and composition for doing so
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Page 12-13, (2008/06/13)
This invention has as its object a process for preparation of vinyl aryl derivatives by an electrochemical path. This process is defined in that it consists in subjecting a composition that comprises a cobalt salt, an aromatic halide and a vinyl ester to the action of a metal that is at least as reducing as zinc. Application to organic synthesis.
New chemical synthesis of functionalized arylzinc compounds from aromatic or thienyl bromides under mild conditions using a simple cobalt catalyst and zinc dust
Fillon, Hyacinthe,Gosmini, Corinne,Perichon, Jacques
, p. 3867 - 3870 (2007/10/03)
A new chemical method for the preparation of arylzinc intermediates is described in acetonitrile, on the basis of the activation of aryl bromides by low-valent cobalt species arising from the reduction of cobalt halide by zinc dust. This procedure allows for the synthesis of a variety of functionalized aryl- and thienylzinc species in good to excellent yields. The versatility and the simplicity of that original method represent an alternative to most known procedures.
New chemical cross-coupling between aryl halides and allylic acetates using a cobalt catalyst
Gomes, Paulo,Gosmini, Corinne,Perichon, Jacques
, p. 1043 - 1045 (2007/10/03)
(Figure presented) The cobalt-catalyzed coupling reaction of aromatic halides and allylic acetates proceeds readily under mild conditions in the presence of the appropriate reducing agent to produce allylaromatic derivatives either in pure acetonitrile (aryl bromides) or in an acetonitrile/pyridine mixture (aryl chlorides).