Heck reaction catalyzed by Pd supported on LDH-F hydrotalcite

LDH-F hydrotalcite was used, for the first time, as an efficient and selective basic support for palladium catalyzed Heck reaction. The ligand-free heterogeneous catalyst Pd/LDH-F exhibits higher activity and selectivity in the Heck reaction of aryl bromides with styrene on small amount of palladium (0.1 mol% of Pd). The higher yields than those previously obtained with Pd containing layered double hydroxides (LDHs) are reached. The catalyst can easily be separated from the reaction mixture and reused after washing without loss in activity. The influence of the highly polarized basic fluoride ions on reaction performance is discussed in this study. Moreover, the influence of several fundamental parameters (nature of support, Mg/Al ratio, property of the Pd complex) on the reactivity is also discussed. (c) 2005 Elsevier B.V. All rights reserved.