An Efficient and Practical Process for Pd/Cu CocatalyzedHomocoupling Reaction of Terminal Alkynes Using Sodium Percarbonate as a Dual Reagent in Aqueous Media

Abstract

A new process for the Pd/Cu co-catalyzed homocoupling reaction of terminal alkynes was developed. The reaction was carried out in aqueous media with sodium percarbonate as both a clean oxidant and a base. Meanwhile, a palladium complex immobilized on a synthetic PS-PEG 400 -PPh 2 resin was used as the catalyst, which may be recovered by simple filtration and reused for several times with high activity.

Chemicals from Alkynes with Palladium Catalysts

“…Examples are the use of a polystyrene-PEG400-PPh 2 as a supported phosphine ligand combined to PdCl 2 (3 mol %) and in the presence of CuI (3 mol %). The reaction was carried out in acetonitrile/water with sodium percarbonate as both an oxidant and a base at room temperature, and the catalyst was recovered by filtration and reused up to five times with a certain decrease in its activity . In addition, the palladium complex anchored to mesoporous silica 306 (1 mol %) promotes the homocoupling of phenylacetylene .…”

Organic transformations catalyzed by palladium nanoparticles on carbon nanomaterials

“…Synthesis of biphenyls 3aa-gc with aryl iodides 1a-g and arylboronic acids 2a-c. a,b polymeric materials, supramolecular structures, natural products and pharmaceuticals. [20][21][22][23][24][25] The first synthesis of symmetric 1,3-diynes through homo-coupling of terminal alkynes was reported by Carl Glaser in 1869 in the presence of Cu(I) salt and oxygen in air. 26,27 Subsequently, Eglinton 28 and Hay 29,30 modified the method to improve the versatility of the method.…”

Heterogeneous Catalytic Homocoupling of Terminal Alkynes

“…Jiang et al developed another palladium–copper cocatalyzed homocoupling of terminal alkynes involving a palladium complex immobilized on a PS-PEG 400 -PPh 2 resin . Sodium percarbonate (3 equiv) was used as the oxidant in aqueous acetonitrile, with the latter playing a key role for the reaction to succeed.…”