Simple haloaldehydes, including enolisable aldehydes, were found to be suitable for the formation of cyclic products by cascade (domino) condensation, cyclisation, dipolar cycloaddition chemistry. This multi-component reaction approach to heterocyclic compounds was explored by using hydroxylamine, a selection of aldehydes, and a selection of activated dipolarophiles. Initial condensation gives ...

The 1,3-dipolar cycloaddition reaction (1,3-DC) has offered the opportunity to produce a wide range of heterocyclic compounds [1,2]. These compounds were used to prepare new molecules of crucial importance for both pharmaceutics and industry sector [3]. The application of 1,3-DC reactions in natural product synthesis is heavily dependent upon an understanding of the regioselectivity and chemios...

A number of nitrones have been synthesized in three different procedures, starting with N-phenyl hydroxylamine, followed by the condensation reaction some selected aldehydes. Furthermore, these were employed preparation a new isoxazolidines. Cycloaddition to styrene produced desired products.

A green and sustainable nitrone formation reaction via visible-light-promoted of aryl diazoacetates with nitrosoarenes is described. This protocol exhibits good functional group tolerance broad substrate scope for both nitrosoarenes. Comparing the reported methods synthesis nitrones from nitrosoarenes, described herein occurs under sole visible-light irradiation without need any catalysts addit...

A highly efficient organocatalytic sequential reaction involving Michael addition of bis(phenylsulfonyl)ethylene, in situ condensation and intramolecular nitrone [3+2] cycloaddition with a variety of aldehydes and hydroxyamines to afford a single diastereomer of indanes with four stereogenic centers in excellent yields and stereoselectivities was developed.

A simple, fast, efficient and eco-friendly procedure was developed for the synthesis of alkyl and aryl-N-methylnitrones. The corresponding nitrones of aromatic aldehydes, aliphatic aldehydes and alicyclic carbonyl compounds were prepared from N-methylhydroxylamine hydrochloride and Na2CO3-Na2SO4 by simply grinding at room temperature without using solvent.

Experimental and theoretical evidence shows that phthalimides are highly efficient single electron transfer acceptors in reactions promoted by samarium diiodide, affording ketyl radical anion intermediates, which participate in high-yielding inter- and intramolecular reductive coupling processes with different radicophiles including imides, oxime ethers, nitrones, and Michael acceptors.

Oxidative transformations of the aldehydes, ketones, and their azomethine derivatives such as hydrazones, Schiff bases, azines, and oximes are presented and discussed. The oxidants used have been hydrogen peroxide in the presence of selenium compounds as catalysts, peroxycarboxylic acids, and eerie ammonium nitrate. Some of reported reactions have practical value in the synthesis of phenols, es...