Polyethylene glycol (PEG)-stabilized palladium nanoparticles were prepared and applied to the selective hydrogenation of 1,5- cyclooctadiene (1,5-COD) in thermoregulated PEG biphase system, which allows a reaction in a single-phase at a higher temperature followed by a phase split at a lower temperature. Under the optimized reaction conditions, the conversion of 1,5-COD and the selectivity of cyclooctene (COE) were 100 and 98%, respectively. The catalyst could be easily separated from the product by phase separation and reused for 6 times without evident loss in activity and selectivity. 2007 Yan Hua Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
Tian Song Huang Yan Hua Wang Jing Yang Jiang Zi Lin Jin
Rh nanoparticles stabilized by PEG-substituted triphenyl-phosphine(PETPP,P[C6H4-p-(OCH2CH2)nOH]3) combining double stabilization effects demonstrated high activity and good recyclability in aqueous biphasic hydrogenation of benzene.The value of turnover frequency(TOF) was 3333 h^-1.Furthermore,the rhodium nanoparticle catalyst could be easily recycled for five times without loss in activity.