Abstract
Two series of bis(imidazolylidene)palladium complexes of general formula [PdBr2(NHC)2] have been prepared. The molecular weight of the complexes was enlarged by bonding poly(benzyl ether) dendrons of increasing size (G0 to G3) at the nitrogen atom of the NHC ligands. Complexes 1–4 contain monodentate NHC ligands coordinated in a trans mode, whereas complexes 9–12 contain a chelating ethylene-bridged bis(NHC) ligand. The complexes were recovered from the product stream of a Mizoroki–Heck reaction by nanofiltration through thermally and chemically stable ceramic membranes. The recoverability is better for larger complexes and chelate ligands. In particular, chelate G3 complex 12 maintained a constant activity during the 13 recovery cycles performed, affording an accumulated turnover number (TON) of 13 000. On average, around 99.5% of the metal is recovered in each recovery cycle, and contamination by palladium is only 3 mg per kg of product. Several models to explain the efficiency of the recovery are discu...
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.