- Iodine(III)-Catalyzed Electrophilic Nitration of Phenols via Non-Br?nsted Acidic NO2+ Generation
-
The first catalytic procedure for the electrophilic nitration of phenols was developed using iodosylbenzene as an organocatalyst based on iodine(III) and aluminum nitrate as a nitro group source. This atom-economic protocol occurs under mild, non-Br?nsted acidic and open-flask reaction conditions with a broad functional-group tolerance including several heterocycles. Density functional theory (DFT) calculations at the (SMD:MeCN)Mo8-HX/(LANLo8+f,6-311+G) level indicated that the reaction proceeds through a cationic pathway that efficiently generates the NO2+ ion, which is the nitrating species under neutral conditions.
- Juárez-Ornelas, Kevin A.,Jiménez-Halla, J. Oscar C.,Kato, Terumasa,Solorio-Alvarado, César R.,Maruoka, Keiji
-
supporting information
p. 1315 - 1319
(2019/03/07)
-
- On the role of nitrogen monoxide (nitric oxide) in the nitration of a tyrosine derivative and model compounds
-
The nitration of tyrosine derivatives with nitrogen monoxide (nitric oxide) occurs only in the presence of dioxygen, and the hypothesized mechanism involves nitrogen dioxide (.NO2). For better understanding of the reaction mechanism, the nitration of model compounds - such as 1- and 2-naphthols and their corresponding 2- and 1-nitroso derivatives with nitrogen monoxide in the presence and in the absence of dioxygen was studied. The results described here show that tyrosine and naphthols do not undergo nitrosation when they react with .NO, and so nitrosation of tyrosine in biological systems is highly unlikely. In addition, the oxidation of nitrosonaphthols ? isonitrosonaphthols by nitric oxide and its derivatives to the corresponding nitro derivatives does not involve the oxoammonium ion, as reported previously. The mechanistic proposals are supported mainly by ESR investigation and electrochemical data. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
- Giorgini, Elisabetta,Petrucci, Rita,Astolfi, Paola,Mason, Ronald P.,Greci, Lucedio
-
p. 4011 - 4017
(2007/10/03)
-
- Oxidation of 1-acyl-2-naphthol oximes: peri- and o-cyclisation and spiro cyclodimerisation of naphthoquinone nitrosomethide intermediates
-
The oxidation of 2-hydroxynaphthaldehyde oxime with lead(IV) acetate (LTA) gave a mixture of naphtho[1,8-de][1,2]oxazine and a spiro dimer. LTA oxidation of 6-bromo (or nitro)-2-hydroxynaphthaldehyde oximes provided only spiro dimers. Similar treatment of (2-hydroxy-1-naphthyl)keto oximes with LTA gave naphtho[1,8-de][1,2]oxazines and benzo[cd]indol-3(1H)-ones. Low temperature oxidation of 1-(2-hydroxy-1-naphthyl)propan-1-one oxime furnished 2-ethylbenzo[cd]indol-3(1H)-one and 1-ethylnaphtho[1,2-d]isoxazole-2-oxide. peri- and o-Naphthoquinone nitrosomethides are invoked as intermediates that undergo peri- and o-cyclisation and intermolecular cyclodimerisation.
- Supsana, Paraskevi,Tsoungas, Petros G,Aubry, André,Skoulika, Stavroula,Varvounis, George
-
p. 3445 - 3453
(2007/10/03)
-