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.

The α-arylation of carbonyl compounds is generally accomplished under basic conditions, both under metal catalysis and via aryl transfer from the diaryl λ(3)-iodanes. Here, we describe an alternative metal-free α-arylation using ArI(O2CCF3)2 as the source of a 2-iodoaryl group. The reaction is applicable to activated ketones, such as α-cyanoketones, and works with substituted aryliodanes. This formal C-H functionalization reaction is thought to proceed through a [3,3] rearrangement of an iodonium enolate. The final α-(2-iodoaryl)ketones are versatile synthetic building blocks.

Five novel generations of phosphorus dendrimers based on a cyclotriphosphazene core with stable TEMPO radicals end groups have been synthesized and studied by EPR, SQUID, 1 H NMR, 31 P NMR, FT-IR, and UV−vis spectroscopy. The nitroxyl radicals exhibit a strong exchange interaction, which depends on the dendrimer generation and the temperature. An |Δm s | = 2 transition has been observed in each generation in dilution conditions demonstrating the intramolecular origin of the radicals interaction. There exists a direct proportionality between the EPR |Δm s | = 2 transition intensity and the number of radicals by generation; consequently, the utility of EPR for the determination of the substitution efficiency on dendrimers by paramagnetic species is quite good. From the UV−vis characterization, we have observed that the molar extinction coefficient value is also proportional to the number of TEMPO groups. The magnetic properties of the zero, first and fourth generation dendrimers studied by SQUID magnetometry show antiferromagnetic interaction between radicals.

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Palladium complexes of a variety of β- and γ-iminophosphines have been prepared and characterized by X-ray diffraction studies. Their properties as catalyst for three different Stille coupling reactions have been investigated and compared to catalytic performances of a phosphorus-containing dendrimer incorporating analogous γ-iminophosphine palladium complexes on the surface.

Electroactive conjugated polymers have been synthesized by electropolymerisation of increasing generations of dendrimers derivatized by peripheral bithiophene groups.