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Novel palladium(II) complexes with oxazolin-2-ylidene ligands have been synthesized via direct reaction of palladium acetate and oxazolium salts, prepared in turn by alkylation of oxazole with methyl iodide or benzylic bromides. The resulting complexes have been characterized and used as catalysts in Heck coupling reactions of aryl bromides, where they exhibit remarkable catalytic activity, higher than that of the closely related bis-imidazolin-2-ylidene and bis-benzothiazolin-2-ylidene complexes.

The chiral fluorous complex tetrakis-dirhodium(II)−(S)-N-(n-perfluorooctylsulfonyl)prolinate has been prepared and used as a catalyst in homogeneous or fluorous biphasic fashion. The catalyst displays good chemo- and enantioselectivity in intermolecular cyclopropanation and C−H bond activation reactions. The catalyst can be simply and thoroughly separated from the reaction mixture and is recyclable.

Removal of an acetato ligand from dirhodium(II) acetato complexes with thioethers of the general structure [Rh2(μ-OAc)4(RSCH2Z)2] yields the cationic complexes [Rh2(μ-OAc)3(RSCH2Z)2](BF4) (R = Me, Ph; Z = C(O)OEt, CH2C(O)OMe). The methylthio complex with Z = C(O)OEt has been structurally characterized and found to exhibit an unusual bidentate O−S coordination of the oxo thioether ligands. Preliminary tests indicate that the complex is a promising catalyst of the silylformylation or hydrosilylation of 1-hexyne with dimethylphenylsilane.

The surface of a solid silica support has been functionalized with long perfluoroalkyl chains. The resulting surface layer readily adsorbs fluorous molecules from organic solutions. In this way, dirhodium(ii) perfluorocarboxylate catalysts can be conveniently immobilized on a solid support. The resulting Bonded Fluorous Phase (BFP) catalysts display a high activity in the silane alcoholysis reaction using a solventless procedure and are easily recycled.

The surface of a solid silica support has been functionalized with long perfluoroalkyl chains. The resulting surface layer readily adsorbs fluorous molecules from organic solutions. In this way, dirhodium(ii) perfluorocarboxylate catalysts can be conveniently immobilized on a solid support. The resulting Bonded Fluorous Phase (BFP) catalysts display a high activity in the silane alcoholysis reaction using a solventless procedure and are easily recycled.

Amorphous WO3films are obtained by using the oxoalkoxide precursor WO(OtBu)4. This compound is easily evaporated at 80 °C, and reacts with water at the surface of the substrate (Si(100) or soda lime glass (KGlass)) to give films of tungsten oxide in a combined CVD sol–gel process. The films deposited at low temperatures (150 °C, Si(100), or 100 °C, KGlass) can be defined as tungstic species (of general formula WOn(OH)m), having interesting electrochromic properties. Thermal treatment at temperatures over 400 °C converts the material to a more typical WO3film.

Amorphous WO3 films, doped with phosphorus, have been synthesized by chemical vapor deposition of volatile, low-melting P-substituted tungsten carbonyls. The presence of a small quantity of dopant released by the precursor during its decomposition is sufficient to inhibit the crystallization of the tungsten oxide on the matrix (P/W 2−4 atom % on Si(100) and ca. 10 atom % on KGlass). The nature of the film is scarcely affected by the experimental conditions of deposition (namely pO2 partial pressure) and the quantity of the P dopant is properly tuned by an appropriate choice of the molecular precursor, being in the order W(CO)4[P(OEt)3]2 (P/W 1/1) > W2(μ-PR2)2(CO)8 (P/W 1/4) > W(CO)4(PEt3)2 (P/W 1/10 on KGlass, 1/30 on Si). The films on KGlass exhibit interesting electrochromic properties with a maximum efficiency of 66 cm²/C.

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The cationic Ni(II) complexes of the type (II) are prepared from the bis(diketonato)‐Ni(II) complexes (I) and corresponding diphosphines (molar ratio 1:1) or diamines (molar ratio 1:2) as shown.

The scheme shows a general and effective synthetic route to the novel complexes (III) which are a O,O'‐bonded species, thermally stable in the solid state and in solution.

The diketo compounds (Ia) and (Ib) undergo SnCl4‐promoted reaction with activated nitriles (II) (R3: COPh, COOEt, CCl3) to give mixtures of the enamino diketo compounds (III) and their deacetylated derivatives (IV).

The macrocyclic complex (I) reacts with cyanogen to give (III) and (IV) in reversible reactions.

The catalytic efficiency of a series of acetylacetonato complexes in the reaction of (I) with (II) is estimated quantitatively.