All reagents and solvents were purchased from Aldrich Chemical Co. and used as received. Benzoxazine 1 was prepared according to the reported procedure, 5c and the purity is >95% as determined by 1 H NMR.Measurements. 1 H NMR spectra were taken on a Bruker AM-360 (360 MHz). Chemical shifts were reported in parts per million relative to TMS as an internal standard (δ TMS = 0) for 1 H NMR spectra. The solvent for NMR measurement was deuterated DMSO or deuterated chloroform. DSC studies were done on a DSC-Q20 thermal analyzer from TA Instruments with N 2 as a purge gas at a scanning rate of 10 °C/min. About 5 mg of samples was tested in high-pressure closed aluminum pans.General Procedures for Ring-Opening Polymerization of Benzoxazine 1. In a test tube, benzoxazine 1 (113 mg, 0.5 mmol) and a catalyst (1 or 5 mol %) were dissolved in acetone (∼0.2 mL). The mixture was dried at room temperature under high vacuum for ∼1 h and heated under the conditions showed above. Then the resulting mixture was subjected to routine analysis.

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A new family of phosphorus dendrimers containing on their surfaces 3, 6, 12, and 96 15-membered azamacrocycles has been synthesized. The coordinating ability of these macrocycles to palladium(0) atoms allowed the preparation of new dendrimers of several generations containing the corresponding metal complexes and several new nanoparticulated materials, 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 new compounds and materials have been characterized by NMR, IR, elemental analysis and/or matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) spectrometry, high-resolution transmission electron microscopy, and electron diffraction. Also UV-vis spectra were obtained. The Mizoroki-Heck reaction has been catalyzed in a homogeneous and heterogeneous manner by using four different materials; in all cases, the catalyst could be recovered and reused several times.