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The use of a new ZnO-supported palladium(0) nanoparticle catalyst for the cyanation of aryl halides using a relatively benign cyanide source, K4[Fe(CN)6], is described. This catalyst has been applied for the efficient cyanation of a variety of functionalized aryl bromides and activated aryl chlorides. This process circumvents the need for an additive and a ligand for the reaction and offers the advantages of high product yields, low catalyst loading (0.2 mol % Pd), and recyclability of the catalyst.

An efficient procedure for the stereoselective synthesis of (E)- and (Z)-2-alkene-4-ynoates and -nitriles by a simple reaction of vic-diiodo-(E)-alkenes with acrylic esters and nitriles catalyzed by in situ prepared Pd(0) nanoparticles in water has been developed. Addition of acrylic esters leads to (E)-isomers exclusively, whereas (Z)-isomers are obtained in high stereoselectivity from reactions of acrylonitrile. The aqueous slurry of Pd nanoparticles is recycled. A probable mechanism has been suggested.

A basic ionic liquid, [bmIm]OH, efficiently promotes a one-pot, three-component condensation of aldehydes, malononitrile, and thiophenols to produce highly substituted pyridines in high yields at room temperature. This reaction does not involve any hazardous organic solvent and toxic catalyst. The ionic liquid is recovered and recycled for subsequent reactions.