68984-28-1Relevant academic research and scientific papers
PHOTOREDOX-CATALYZED DIRECT C-H FUNCTIONALIZATION OF ARENES
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Paragraph 00378; 00379, (2017/01/31)
The invention generally relates to methods of making substituted arenes via direct C-H amination. More specifically, methods of making para- and ortho-substituted arenes via direct C-H amination are disclosed. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.
Site-selective arene C-H amination via photoredox catalysis
Romero, Nathan A.,Margrey, Kaila A.,Tay, Nicholas E.,Nicewicz, David A.
, p. 1326 - 1330 (2015/10/12)
Over the past several decades, organometallic cross-coupling chemistry has developed into one of the most reliable approaches to assemble complex aromatic compounds from preoxidized starting materials. More recently, transition metal-catalyzed carbon-hydrogen activation has circumvented the need for preoxidized starting materials, but this approach is limited by a lack of practical amination protocols. Here, we present a blueprint for aromatic carbon-hydrogen functionalization via photoredox catalysis and describe the utility of this strategy for arene amination. An organic photoredox-based catalyst system, consisting of an acridinium photooxidant and a nitroxyl radical, promotes site-selective amination of a variety of simple and complex aromatics with heteroaromatic azoles of interest in pharmaceutical research. We also describe the atom-economical use of ammonia to form anilines, without the need for prefunctionalization of the aromatic component.
Cu(OAc)2·H2O-catalyzed N-arylation of nitrogen-containing heterocycles
Xu, Zhong-Lin,Li, Hong-Xi,Ren, Zhi-Gang,Du, Wei-Yuan,Xu, Wei-Chang,Lang, Jian-Ping
supporting information; experimental part, p. 5282 - 5288 (2011/08/04)
In the absence of any additional ligands, the efficient N-arylation of nitrogen-containing heterocycles with aryl iodides catalyzed by relative low catalyst amount of Cu(OAc)2·H2O was developed. This simple catalytic system is involved in the C-N cross-coupling reaction and works for a variety of pyrazole, pyrrole, imidazole, triazole, indole, benzoimidazole, benzotriazole, carbazole, and anilines as well as aryl iodides with different electronic properties. Highly efficient copper(II)-catalyzed N-arylation protocol was established.
An efficient synthesis of 4-aryl-4H-[1,2,4]triazoles under microwave irradiation in dry media
Woisel,Cazier,Surpateanu,Baudel,Boursier
, p. 71 - 74 (2007/10/03)
A microwave-enhanced synthesis of 4-aryl-4H-[1,2,4]triazole under solvent free conditions is described. The yields and especially the reaction time are noticeably improved in comparison with conventional heating.
Azocoupling of Quaternary 1,2,4-Triazolium Salts to Form 5-p-N,N-Dimethylaminophenylazo-1,2,4-triazolium Salts
Becker, H. G. O.,Hoffmann, Gerda,Gwan, Kim Mun,Knuepfer, L.
, p. 325 - 337 (2007/10/02)
Quaternary 1,2,4-triazolium salts 1 couple easily with p-N,N-dimethylamino-benzenediazonium salts to form azodyes 3 (5-N,N-dimethylaminophenylazo-1,2,4-triazolium salts), preferably under solid-liquid phase transfer conditions using chloroform or methylene chloride and triethylamine or DABCO.Zwitterionic 1,2,4-triazolium salts (anhydro mercapto hydroxide, anhydro hydroxy hydroxide, and anhydro anilido hydroxide ("nitron")) couple as well.The azodyes - as also well known from industrially used types - absorb in the region of 500 nm and have high extinction coefficients.Substituents in 1-, 3- or 4-position of the triazolium ring exert no clear substituent effects.The quaternary 1,2,4-triazolium salts were synthesized according to standard procedures.
