55233-49-3Relevant academic research and scientific papers
A Biphilic Phosphetane Catalyzes N-N Bond-Forming Cadogan Heterocyclization via PIII/PV = O Redox Cycling
Nykaza, Trevor V.,Harrison, Tyler S.,Ghosh, Avipsa,Putnik, Rachel A.,Radosevich, Alexander T.
supporting information, p. 6839 - 6842 (2017/05/29)
A small-ring phosphacycle, 1,2,2,3,4,4-hexamethylphosphetane, is found to catalyze deoxygenative N-N bond-forming Cadogan heterocyclization of o-nitrobenzaldimines, o-nitroazobenzenes, and related substrates in the presence of hydrosilane terminal reductant. The reaction provides a chemoselective catalytic synthesis of 2H-indazoles, 2H-benzotriazoles, and related fused heterocyclic systems with good functional group compatibility. On the basis of both stoichiometric and catalytic mechanistic experiments, the reaction is proposed to proceed via catalytic PIII/PV = O cycling, where DFT modeling suggests a turnover-limiting (3+1) cheletropic addition between the phosphetane catalyst and nitroarene substrate. Strain/distortion analysis of the (3+1) transition structure highlights the controlling role of frontier orbital effects underpinning the catalytic performance of the phosphetane.
A Facile One-Step Synthesis of 2-Arylindazoles via Reductive Cyclization of N-(2-nitroarylidene)amines
Lin, Wei,Hu, Minghua,Feng, Xian,Cao, Chengpao,Huang, Zhibin,Shi, Daqing
, p. 1170 - 1174 (2015/08/06)
A mild and efficient synthesis of 2-arylindazole derivatives via the reductive cyclization of nitro-aryl substrates mediated by a low-valent titanium reagent (TiCl4/Sm/Et3N) has been developed. The attractive features of the current method include an N-N bond formation and the selective reduction of the =C-N bond and nitro group, both of which were easily achieved in one-pot by controlling the pH of the reaction mixture.
Microwave-assisted molybdenum-catalyzed reductive cyclization of o -nitrobenzylidene amines to 2-Aryl-2 H -indazoles
Moustafa, Ahmed H.,Malakar, Chandi C.,Aljaar, Nayyef,Merisor, Elena,Conrad, Jürgen,Beifuss, Uwe
supporting information, p. 1573 - 1577 (2013/08/23)
The reductive cyclization of o-nitrobenzylidene amines under microwave conditions employing MoO2Cl2(dmf)2 as catalyst and Ph3P as reducing agent delivers 2-aryl-2H-indazoles with yields ranging from 61-92%. Georg Thieme Verlag Stuttgart. New York.
Oriented synthesis and in vitro anticancer activity of biquinazoline-2,2'- diones
Dou, Guolan,Shi, Daqing,Li, Yonghai
scheme or table, p. 195 - 199 (2010/11/02)
The synthesis of a series of biquinazoline-2,2'-diones starting from o-nitrobenzaldehydes, anilines, and triphosgene is presented. This general approach features a novel and easy way for access to the target products. The mechanistic course of the reaction suggests the involvement of reduction, coupling, and cyclization by one-pot. These compounds were also investigated in vitro for anticancer activity, and some were found to have good anticancer activity.
