文摘
A new family of phosphorus dendrimers containing on their surfaces 3, 6, 12, and 96 15-membered azamacrocycleshas been synthesized. The coordinating ability of these macrocycles to palladium(0) atoms allowed the preparationof new dendrimers of several generations containing the corresponding metal complexes and several new nanoparticulatedmaterials, where nanoparticles are stabilized mainly by the complexed dendrimers of the zero, first, and fourth generations.No reduction process of palladium(II) salts was needed to prepare nanoparticles of 2.5-7.9 nm diameter. All the newcompounds and materials have been characterized by NMR, IR, elemental analysis and/or matrix-assisted laser desorptionionization time-of-flight (MALDI-TOF) spectrometry, high-resolution transmission electron microscopy, and electrondiffraction. Also UV-vis spectra were obtained. The Mizoroki-Heck reaction has been catalyzed in a homogeneousand heterogeneous manner by using four different materials; in all cases, the catalyst could be recovered and reusedseveral times.