223520-89-6Relevant academic research and scientific papers
Visible-Light-Induced C(sp2)-P Bond Formation by Denitrogenative Coupling of Benzotriazoles with Phosphites
Jian, Yong,Chen, Ming,Huang, Binbin,Jia, Wei,Yang, Chao,Xia, Wujiong
, p. 5370 - 5374 (2018/09/13)
A visible-light-induced denitrogenative phosphorylation of benzotriazoles is presented, in which diverse substituted aryl phosphonates could be obtained in good to excellent yields. This efficient protocol exhibits good tolerance with various functional g
Synthesis of 1H-1,3-benzazaphospholes: Substituent influence and mechanistical aspects
Heinicke, Joachim,Gupta, Nidhi,Surana, Anushka,Peulecke, Normen,Witt, Brigitte,Steinhauser, Kinga,Bansal, Raj K,Jones, Peter G
, p. 9963 - 9972 (2007/10/03)
Various substituted carboxylic acid 2-chloro- and 2-bromoanilides 1a-j react with triethylphosphite in the presence of anhydrous NiCl2 or NiBr2 to give o-acylamido-benzenephosphonic acid esters 2a-g and 2j. Yields depend strongly on the substituents. 2-Fluoro-4,6-dibromoacetanilide 1g reacts only at 6-position, indicating an o-directed process. Based on substituent effects, we infer a mechanism via Ni(0) intermediates that insert into the carbon-halogen bond. The N-tertiary 2-bromoformanilide 4 does not undergo phosphonylation to 5 in the presence of the Ni-catalyst but reacts in the presence of Pd-catalysts. The subsequent reduction of the N-secondary o-acylamido-benzenephosphonic acid esters 2 with excess LiAlH4 is coupled with an intramolecular cyclisation to the 1H-1,3-benzazaphospholes 6 whereas the N-tertiary derivative 5 does not undergo cyclisation upon reduction. NMR data and the crystal structure of 6d are reported.
1H-1,3-benzazaphospholes: The organometallic route and a new three-step synthesis with reductive ring closure
Bansal, Raj K.,Gupta, Neelima,Heinicke, Joachim,Nikonov, George N.,Saguitova, Farida,Sharma, Dinesh C.
, p. 264 - 269 (2007/10/03)
Primary and N-secondary 2-phosphanylanilines were synthesized via metallation of 2-bromoanilines, coupling with CIP(NMe2)2, alcoholysis and reduction with LiAlH4, and subsequently reacted with formimidoester hydrochloride to give 1,3-benzazaphospholes. For 1H-1,3-benzazaphospholes, a shorter alternative three-step synthesis was developed, based on N-acylation of 2-bromoaniline, NiCl2-catalyzed arylation of triethyl phosphite and a new reductive cyclization of amidophosphonic acid ester with excess LiAlH4.
