Gold-catalyzed syntheses of 2,3-disubstituted indole derivatives from N-hydroxyanilines and allenes are described; these reactions require benzaldehyde as an additive to generate nitrones in situ. Our control experiments indicate that nitrones and water were indispensable in the reactions whereas N-hydroxyanilines alone were inactive nucleophiles. This synthetic method is compatible with allene...

A series of 1,3-dipolar cycloaddition reactions are carried out using cyclodimers of simple nitrones and various dipolarophiles; substituted isoxazolidines are isolated and identified. It is proved that such cyclodimers, in solution, are in equilibrium with their corresponding nitrones and enamines. It is also concluded that aldocyclodimers are more potent than keto-cyclodimers in establish...

A theoretical study based on (U)M06-2X/cc-pVTZ calculations has been used to investigate the [3 + 3] thermal dimerization of nitrones to 1,4,2,5-dioxadiazinanes in both the gas phase and in dichloromethane solution. Calculations suggest that dimerization of nitrones takes place through a concerted mechanism involving a formal disallowed [4π + 4π] cycloaddition with a free energy barrier of 30.8...

Regioselective additions of pyrroles to a variety of optically active nitrones under smooth acidic conditions lead to chiral pyrrolic N-hydroxylamines in good to excellent yields. Depending on the position of the chirality on the nitrone partner, the addition products have been isolated with high diastereoselectivity levels. Reaction of glyoxylate based chiral nitrones either at the C-2 or at t...

1,3-Dipolar cycloaddition of dihydropyran derived nitrones synthesized from 2,3 dihydro 4H-pyran and various hydroxylamines, with electron deficient alkynes are found to have significant rate acceleration and improved yields of isoxazolines in 1-Butyl-3-methylimidazolium based ionic liquids while with enals exclusively endo isoxazolidines are obtained with high selectivity. Synthetic potentiali...

Gold-catalyzed 1,2-iminonitronation of propiolate derivatives with nitrosoarenes to give α-imidoyl nitrones is described; this new reaction is applicable to diverse propiolate derivatives and nitrosoarenes.

The first example of a regioselective and organocatalyzed 1,3-dipolar cycloaddition reaction between conjugated alkynoates and nitrones "on water" is described.

Running title: Metabolism of cyclic nitrone superoxide adducts Manuscript Click here to view linked References 2 Abstract Reactive oxygen species (ROS) are by-products of aerobic metabolism involved in the onset and evolution of various pathological conditions. Among them, superoxide radical is of special interest as the origin of several damaging species such as H 2 O 2 , hydroxyl radical, or ...

Trifluoromethyl vinyl sulfide, a potential building block for pharmaceutically and agrochemically relevant products, is prepared and used for the first time in high-pressure-mediated 1,3-dipolar cycloaddition reactions with nitrones to synthesize (trifluoromethyl)sulfanyl isoxazolidines.