82632-11-9Relevant academic research and scientific papers
Synthesis of P-Substituted 5- And 6-Membered Benzo-Phostams: 2,3-Dihydro-1 H-1,2-benzazaphosphole 2-Oxides and 2,3-Tetrahydro-1 H-1,2-benzazaphosphinine 2-Oxides
Sabourin, Axel,Dufour, Jeremy,Vors, Jean-Pierre,Bernier, David,Montchamp, Jean-Luc
, p. 14684 - 14694 (2021/10/25)
Several approaches were developed for the preparation of phosphorus-substituted 5- and 6-membered benzophostams. Carbodiimide-promoted cyclization of zwitterionic aminophosphinates derived from a nitrobenzene precursor accomplished the cyclization in good
Organophosphorus Compounds. XIX. Synthesis of 2,3-Dihydro-1H-1,2-benzazaphosphole 2-Oxides, Variously Substituted on Nitrogen and Phosphorus, by N-P Cyclization of Zwitterionic Intermediates
Collins, David J.,Drygala, Peter F.,Swan, John M.
, p. 2517 - 2536 (2007/10/02)
2-Phenyl-2,3-dihydro-1H-1,2-benzazaphosphole 2-oxide (7a) was prepared by thermolysis of the corresponding zwitterionic amino phosphinic acid (4), or its hydrochloride salt (1).Thermolysis of methyl (2-aminobenzyl)phenylphosphinate (5a) was accompanied by intermolecu;ar O->N transmethylation to give, after cyclization, 1-methyl-2-phenyl-2,3-dihydro-1H-1,2-benzazaphosphole 2-oxide (9a); similarly, the ethyl ester (5b) gave the N-ethyl heterocycle (9b). Reaction of 2-phthalimidobenzyl bromide (13a) with diethyl methylphosphonite (14b) gave ethyl (2-phthalimidobenzyl)methylphosphinate 15a).Hydrolysis of (15a) afforded (2-aminobenzyl)-methylphosphinic acid (16), and thermolysis of this produced 2-methyl-2,3-dihydro-1H-1,2-benzazaphosphole 2-oxide (18a). 1-Methyl-2-methoxy-2,3-dihydro-1H-1,2-benzazaphosphole 2-oxide (24) was synthesized in an analogous manner. Base catalyzed N-alkylation of the benzazaphosphole derivatives (7a) and (18a) was readily achieved, and the interconversion of 2-oxides and 2-sulfides was accomplished by conventional methods.
ORGANOPHOSPHORUS COMPOUNDS XVI. SYNTHESIS OF SOME NOVEL 2,3-DIHYDRO-1H-1,2-BENZAZAPHOSPHOLE 2-OXIDES AND -SULPHIDES
Collins, David J.,Drygala, Peter F.,Swan, John M.
, p. 1117 - 1120 (2007/10/02)
Several derivatives of 2,3-dihydro-1H-1,2-benzazaphosphole, a new class of benz-fused N-P heterocycle, have been synthesised by thermal and DCC-promoted N-P ring closure from zwitterionic intermediates.
