Syntheses of heterocyclic compounds. Part XXV. Action of acid on NN-disubstituted o-nitroanilines: benzimidazole N-oxide formation and nitro-group rearrangements

Synthesis of Indolines via a SmI2 Promoted Domino Nitro Reduction–Intramolecular aza‐Michael Reaction

“…The crude product was purified by flash column chromatography on silica gel (5–50% EtOAc in hexane) to give substituted 2‐(2‐nitrophenyl)ethanol 1a , 1b , 1c , 1d , 1e . Spectroscopic data are in accordance with reported values: 1a , 1b , 1c , 1d , and 1e .…”

Quimioterapia da doença de Chagas: estado da arte e perspectivas no desenvolvimento de novos fármacos

“…70 Com o intuito de aumentar a diversidade química e melhorar algumas propriedades físico-químicas desta classe de compostos, as estratégias de ciclização de o-nitro-anilinas e de reação de derivados de benzofuroxanos com 2-bromoacetato, iodeto de pentila e nitroalcanos foram empregadas com sucesso. 71 Na primeira estratégia, a ciclização térmica de onitro-anilinas catalisada por ácido conduziu a uma série de derivados N-óxido1H-benzimidazóis (35)(36)(37)(38)(39) …”

Direct photolysis mechanism of pesticides in water

“…4) From the photochemistry of N,N-disubstituted 2-nitroanilines, 183) two mechanisms can be postulated: an excited nitro oxygen abstracts hydrogen from an N-alkyl moiety, and the resulting biradical is cyclized; oxygen transfers from the excited nitro group to the N-alkyl nitrogen, followed by cyclization. Chloridazon was first dimerized in aqueous photolysis via the intermolecular nucleophilic attack of the amino nitrogen at the Cl-bearing carbon, followed by the intramolecular cyclization between the remaining same sites, 184) probably by the S N (ET) Ar* mechanism as described in the previous section.…”