19755-53-4Relevant articles and documents
Transition-metal-free decarboxylative halogenation of 2-picolinic acids with dihalomethane under oxygen conditions
Zhang, Xitao,Feng, Xiujuan,Zhang, Haixia,Yamamoto, Yoshinori,Bao, Ming
supporting information, p. 5565 - 5570 (2019/10/22)
A convenient and efficient method for the synthesis of 2-halogen-substituted pyridines is described. The decarboxylative halogenation of 2-picolinic acids with dihalomethane proceeded smoothly via N-chlorocarbene intermediates to afford 2-halogen-substituted pyridines in satisfactory to excellent yields under transition-metal-free conditions. This new type of decarboxylative halogenation is operationally simple and exhibits high functional-group tolerance.
Synthesis and biological evaluation of N-arylbenzo[b]thieno[3,2-d] pyrimidin-4-amines and their pyrido and pyrazino analogues as Ser/Thr kinase inhibitors
Loidreau, Yvonnick,Marchand, Pascal,Dubouilh-Benard, Carole,Nourrisson, Marie-Renée,Duflos, Muriel,Lozach, Olivier,Loa?c, Nadège,Meijer, Laurent,Besson, Thierry
, p. 171 - 183 (2013/02/22)
A useful and rapid access to libraries of N-arylbenzo[b]thieno[3,2-d] pyrimidin-4-amines and their pyrido and pyrazino analogues was designed and optimized for the first time via microwave-accelerated condensation and Dimroth rearrangement of the starting anilines with N′-(2-cyanoaryl)-N,N- dimethylformimidamides obtained by reaction of thiophene precursors with dimethylformamide dimethylacetal. The inhibitory potency of the final products against five protein kinases (CDK5/p25, CK1δ/ε, GSK3α/β, DYRK1A and CLK1) was estimated. N-arylpyrido[3′,2′:4,5]thieno[3,2-d] pyrimidin-4-amine series of compounds (4a-j) turned out to be particularly promising for the development of new pharmacological inhibitors of CK1 and CLK1 kinases.
Nitrosation of aryl and heteroaryltrifluoroborates with nitrosonium tetrafluoroborate
Molander, Gary A.,Cavalcanti, Livia N.
experimental part, p. 4402 - 4413 (2012/06/18)
Organotrifluoroborates have emerged as an alternative to toxic and air- and moisture-sensitive organometallic species for the synthesis of functionalized aryl and heteroaryl compounds. It has been shown that the trifluoroborate moiety can be easily converted into a variety of different substituents in a late synthetic stage. In this paper, we disclose a mild, selective, and convenient method for the ipso-nitrosation of organotrifluoroborates using nitrosonium tetrafluoroborate (NOBF4). Aryl- and heteroaryltrifluoroborates were converted into the corresponding nitroso products in good to excellent yields. This method proved to be tolerant of a broad range of functional groups.
Efficient one-pot transformation of aminoarenes to haloarenes using halodimethylisulfonium halides generated in situ
Baik, Woonphil,Luan, Wanqiang,Lee, Hyun Joo,Yoon, Cheol Hun,Koo, Sangho,Kim, Byeong Hyo
, p. 213 - 219 (2007/10/03)
Halodimethylsulfonium halide 1, which is readily formed in situ from hydrohaloic acid and DMSO, is a good nucleophilic halide. This activated nucleophilic halide rapidly converts aryldiazonium salt prepared in situ by the same hydrohaloic acid and nitrite ion to aryl chlorides, bromides, or iodides in good yield. The combined action of nitrite ion and hydrohaloic acid in DMSO is required for the direct transformation of aromatic amines, which results in the production of aryl halides within 1 h. Substituted compounds with electron-donating or -withdrawing groups or sterically hindered aromatic amines are also smoothly transformed to the corresponding aromatic halides. The only observed by-product is the deaminated arene (usually 7%). The isolated aryldiazonium salts can also be converted to the corresponding aryl halides using 1. The present method offers a facile, one-step procedure for transforming aminoarenes to haloarenes and lacks the environmental pollutants that usually accompany the Sandmeyer reaction using copper halides.
Synthesis of novel halopyridinylboronic acids and esters. Part 2: 2,4, or 5-Halopyridin-3-yl-boronic acids and esters
Bouillon, Alexandre,Lancelot, Jean-Charles,Collot, Valerie,Bovy, Philippe R.,Rault, Sylvain
, p. 3323 - 3328 (2007/10/03)
This paper describes a general method for the synthesis and the isolation of novel 2,4, or 5-halopyridin-3-yl-boronic acids and esters 4, 7, 10, 13, 15. These compounds are prepared taking into account a regioselective halogen-metal exchange using nBuLi or a regioselective ortho-lithiation using lithium diisopropylamide and subsequent quenching with triisopropylborate starting from appropriate mono or dihalopyridines. All substrates studied to date provided a single regioisomeric boronic acid or ester product. Additionally, these compounds have been found to undergo Pb-catalyzed coupling with a range of arylhalides and authorize a strategy to produce new pyridines libraries.
