RESUMO
A high yielding, batch mode synthesis of diaryl ethers and sulfides by an S(N)Ar fluoride-mediated process in scCO(2) has been developed; the use of a polymer-supported imidazolium fluoride reagent in batch mode led to the development of a fixed-bed continuous flow process, with high conversions.
Assuntos
Dióxido de Carbono/química , Éteres/síntese química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico , Éteres/química , Fluorbenzenos/química , Estrutura Molecular , Pressão , Sulfetos/síntese química , Sulfetos/químicaRESUMO
Suzuki cross-coupling reactions are effected in both conventional organic solvents, under continuous flow conditions at 70 degree C, and in batch mode in supercritical carbon dioxide (scCO2), at temperatures as low as 40 degrees C in the presence of palladium(II) acetate microencapsulated in polyurea [PdEnCat] and tetra-n-butylammonium salts.
Assuntos
Acetatos/química , Compostos de Bifenilo/síntese química , Compostos Organometálicos/química , Polímeros/química , Compostos de Amônio Quaternário/química , Compostos de Bifenilo/química , Dióxido de Carbono/química , Catálise , Estrutura Molecular , Sais/química , TemperaturaRESUMO
Palladium(II) acetate microencapsulated in polyurea (MC-[Pd]) is an economical and versatile heterogeneous catalyst for a range of phosphine-free cross-coupling reactions in both conventional solvents and supercritical carbon dioxide (scCO2); the catalyst can be recovered by a simple filtration and recycled up to four times.