A Green Approach for Copper-Free Sonogashira Reaction of Aryl Halides with Phenylacetylene in the Presence of Nano-Pd/Phosphorylated Silica (SDPP/Pd0)

Abstract

Silicadiphenyl phosphinite (SDPP) is used as the solid support for the generation of nano SDPP/Pd(0) from Pd II as precatalyst. This nano catalyst was used for the efficient copper-free Sonogashira reaction of aryl halides in PEG-200 as a solvent. The nano Pd(0) that can be used as pre-prepared or as in situ-generated catalyst exhibited excellent reactivity and stability in the Sonogashira cross-coupling reactions with different aryl iodides, bromides, and also chlorides. This heterogeneous catalyst can be easily recovered and reused in several runs. The use of PEG as solvent and K 2 CO 3 as inorganic base together with the heterogeneous nature of the reaction can be considered as green conditions for this reaction.

Phosphinite-functionalized silica and hexagonal mesoporous silica containing palladium nanoparticles in Heck coupling reaction: synthesis, characterization, and catalytic activity

“…The application of phosphinites as heterogeneous systems in coupling reactions is miniscule even though the homogeneous catalytic processes have been thoroughly explored. Examples of heterogeneous systems on organic or inorganic supports are as follows: a set of phosphorus ligands on a polystyrene support, 15 polyacrylamide containing phosphinite ligand supporting palladium nanoparticles, 16 aminophosphinites ligands supported on Wang resin, 17 phosphinated poly(vinyl alcohol), 18 modied Merrield resin containing PCP-pincer ligand, 19 diphenylphosphinite cellulose, 20 silicadiphenylphosphinite (SDPP) ligands 21,22 and phosphine functionalized magnetic nanoparticles. 23 The inuence of these ligands over palladium, providing both stability and increased reactivity, is the key to their effective use in the formation of C-C bonds.…”