1246929-45-2Relevant academic research and scientific papers
Synthesis of 4-substituted pyrazole-3,5-diamines: Via Suzuki-Miyaura coupling and iron-catalyzed reduction
Tomanová, Monika,Jedinák, Luká?,Ko?a?, Jan,Kvapil, Lubomír,Hradil, Pavel,Canka?, Petr
supporting information, p. 10200 - 10211 (2017/12/26)
A general and efficient synthesis of 4-substituted-1H-pyrazole-3,5-diamines was developed to access derivatives with an aryl, heteroaryl, or styryl group, which are otherwise relatively difficult to prepare. The first step is based on the Suzuki-Miyaura cross-coupling reaction utilizing the XPhos Pd G2 precatalyst. The coupling reactions of 4-bromo-3,5-dinitro-1H-pyrazole with the electron-rich/deficient or sterically demanding boronic acids enabled the production of the corresponding dinitropyrazoles. The subsequent iron-catalyzed reduction of both nitro groups with hydrazine hydrate accomplished the synthesis. The additional demethylation of the 4-methoxystyryl derivative allowed the production of the carboanalog of CAN508 reported as a selective CDK9 inhibitor.
Nitropyrazoles 15.* Synthesis and some transformations of 1-(2,4-dinitrophenyl)-4-methyl-3,5-dinitropyrazole
Zaitsev,Vatsadze,Dalinger,Kachala,Nelyubina,Shevelev
experimental part, p. 2109 - 2117 (2011/01/11)
The method for preparation of 1-(2,4-dinitrophenyl)-4-methyl-3,5- dinitropyrazole has been developed. Due to the larger CH-acidity of 4-Me-group compared to 1,4-dimethyl-3,5-dinitropyrazole, 1-(2,4-dinitrophenyl)-4-methyl-3, 5-dinitropyrazole is capable of reacting with substituted benzaldehydes to afford 4-[(E)-2-arylvinyl]-1-(2,4-dinitrophenyl)-3,5-dinitropyrazoles. Under the action of nucleophiles, dinitrophenyl group is detached from the former compounds leading to previously unknown N-unsubstituted 4-[(E)-2-arylvinyl]-3,5- dinitropyrazoles.
