14336-17-5Relevant academic research and scientific papers
Ruthenium(II)-catalyzed C-H arylation of azoarenes by carboxylate assistance
Hubrich, Jonathan,Himmler, Thomas,Rodefeld, Lars,Ackermann, Lutz
, p. 4089 - 4093 (2015)
Ruthenium(II)carboxylate complexes enabled the unprecedented direct C-H arylation of azoarenes with aryl halides through chelation assistance. The mild reaction conditions of the optimized C-H functionalization process resulted in a remarkable functional
Photocatalysis Enabling Acceptorless Dehydrogenation of Diaryl Hydrazines at Room Temperature
Sahoo, Manoj K.,Saravanakumar, Krishnasamy,Jaiswal, Garima,Balaraman, Ekambaram
, p. 7727 - 7733 (2018/07/25)
Aromatic azo compounds are privileged structural motifs, and they exhibit a myriad of pharmaceutical as well as industrial applications. Here, we report a catalytic acceptorless dehydrogenation of diarylhydrazine derivatives to access a wide variety of aryl-azo compounds with the removal of molecular hydrogen as the sole byproduct. This distinctive reactivity has been achieved under dual catalytic conditions by merging the visible-light active [Ru(bpy)3]2+ as the photoredox catalyst and Co(dmgH)2(py)Cl as the proton-reduction catalyst. The reaction proceeds smoothly under very mild and benign conditions and operates at ambient temperature. This dual catalytic approach is highly compatible with many different functional groups and has a broad substrate scope. We have also demonstrated the reversible hydrogen storage and release phenomenon on hydrazobenzene/azobenzene couple to show the utility of these compounds as hydrogen storage materials. Further diversification of azobenzene was shown by a transition-metal-catalyzed azo-group-directed ortho-C-H bond functionalization.
METHOD FOR PRODUCING BIPHENYLAMINES FROM AZOBENZENES BY RUTHENIUM CATALYSIS
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Paragraph 0097; 0098; 0099, (2017/12/27)
The present invention relates to a novel method for preparing substituted biphenylamines
Palladium-Catalyzed Carbonylative Cyclization of Azoarenes
Wang, Zechao,Yin, Zhiping,Zhu, Fengxiang,Li, Yahui,Wu, Xiao-Feng
, p. 3637 - 3640 (2017/10/13)
In this communication, we established an interesting palladium-catalyzed carbonylation protocol for the intramolecular cyclization of azoarenes. With Mo(CO)6 as the solid CO source and through C(sp2)?H bond activation, a series of azoarenes were transformed into the corresponding 2-arylindazolones in moderate to good yields. Notably, not only symmetrical azoarenes, but also unsymmetrical substrates underwent the reaction with excellent regioselectivity.
Palladium-Catalyzed sp2 C-H Arylation of Azoarenes with Arylhydrazines
Li, Mingyang,Ye, Yong
, p. 4137 - 4142 (2015/12/26)
Transition-metal-catalyzed direct functionalization of C-H bonds is important for new compound synthesis, but usually needs special reagents and harsh conditions. With the aid of an azo directing group, the palladium-catalyzed ortho-sp2 C-H bond activation of azoarenes with hydrazines has been explored. In the reaction, the Pd catalyst reacts with azobenzene to form a palladacyclic intermediate, which reacts with a phenyl radical generated from phenylhydrazine under heating and oxygen to produce a PdIV or PdIII intermediate. This finally undergoes reductive elimination to give the ortho-arylated products with the release of the PdII catalyst. This reaction provides a novel access to ortho-aryl azoarenes under mild conditions in high yield. Helpful hydrazines: With the aid of an azo directing group, the palladium-catalyzed ortho-sp2 C-H bond activation of azoarenes with hydrazines has been explored. The catalyst reacts with azobenzene to form a palladacyclic intermediate, which reacts with a phenyl radical generated from phenylhydrazine produce a PdIV or PdIII intermediate. This undergoes reductive elimination to give the ortho-arylated products and regenerate the catalyst. This reaction provides a novel access to ortho-aryl azoarenes under mild conditions in high yield.
Palladium-catalyzed ortho-functionalization of azoarenes with aryl acylperoxides
Qian, Cheng,Lin, Dongen,Deng, Yuanfu,Zhang, Xiao-Qi,Jiang, Huanfeng,Miao, Guang,Tang, Xihao,Zeng, Wei
, p. 5866 - 5875 (2014/08/05)
With the aid of an azo directing group, Pd-catalyzed ortho-sp2 C-H bond activation/functionalization of azoarenes with aryl acyl peroxides has been explored. This transformation provides easy access to regioselectively introducing acyloxyl and aryl groups into azoarenes by simply changing the reaction temperature and solvent. This journal is the Partner Organisations 2014.
Polar Effects in Reactions of Carbon-Centered Radicals with Diazonium Salts: Free-Radical Diazocoupling
Minisci, Francesco,Coppa, Fausta,Fontana, Francesca,Pianese, Giuseppe,Zhao, Lihua
, p. 3929 - 3933 (2007/10/02)
Carbon-centered radicals react with diazonium salts by addition, leading under reductive conditions to azo derivatives (free-radical diazocoupling), or by electron-transfer in chain processes.The reaction is highly sensitive to polar effects and it has been investigated by three different processes: (i) alkyl radicals, generated from alkyl iodides, H2O2, Fe(II) salt, and DMSO, have been utilized to develop a new general synthesis of alkylarylazo compounds; (ii) the reaction of aryl radicals with diazonium salts in the presence of Ti(III) or Fe(II) salts has been investigated, also in relation to the fact that the reaction products (azoarenes and biaryls) are often detected as side products in classical organic reactions of diazonium salts, catalyzed by Cu(I) salts, such as the Sandmeyer, Meerwein, and Pschorr reactions; (iii) adducts from addition of aryl radicals to vinyl acetate or vinyl ether react with diazonium salts either by diazocoupling reaction or by electron-transfer; a general synthesis of arylazo compounds has been developed.
