A novel approach has been developed for the synthesis of a wide range of α-ketoacetals by the reaction of alkyl/aryl methyl ketones and aliphatic alcohols in the presence of selenium dioxide catalyzed by p -toluenesufonic acid. This method represents a general route to obtain a wide variety of α-ketoacetals in a simple, rapid, and practical manner. This approach is particularly attractive because of the easy availability of the starting materials, mild reaction temperature, and good yields of the products. The resulting α-ketoacetals are of much synthetic value as organic intermediates.

A general strategy for the preparation of N, N-dialkyl-2-oxo-2-arylethaneselenoamides is described. The single step method involves direct coupling of aryl methyl ketones with secondary amines and selenium dioxide in DMSO. The reactions proceeded smoothly at room temperature to provide a number of the α-oxo-selenoamides in good to excellent yields.

Single-crystal XRD data of 3a and copies of 1 H and 13 C NMR of all synthesized compounds (PDF)Accession Codes CCDC 2041476 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk

A metal-free three-component coupling reaction of aryl alkyl/alkyl ketones, SeO 2 , and phenols/anisoles is described. This multicomponent reaction provides a straightforward and facile pathway for the synthesis of α-((4-hydroxy/methoxyphenyl)selanyl)-aryl alkyl/ alkyl ketones in the presence of p-toluenesulfonic acid for the C−Se bond formation process. The method offers an attractive and simple procedure using commonly available shelf reagents to deliver organoselenides that, to our knowledge, are being reported here for the first time.

An efficient method for the synthesis of α,β-unsaturated α′-bromoketones and α,β-unsaturated α′,α′-dibromoketones is described using N-bromosuccinimide (NBS) as the brominating agent mediated by selenium dioxide (SeO2) in the presence of p-toluenesulfonic acid (PTSA) monohydrate in toluene. The method is simple, employing easily available shelf reagents to afford a wide range of products in good yields. The method highlighted that simple fine-tuning of the reaction conditions and molar equivalents of the reactants easily affords either mono- or dibrominated products in excellent yields. A number of these products have not been reported in the literature. All of the reactions were carried out in gram-scale quantities.