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The changes in the surface wettability of many materials are receiving increased attention in recent years. It is not too hard to fabricate resistant hydrophobic surfaces through products bearing both hydrophobic and reactive hydrophilic end groups. More challenging is obtaining resistant nonwetting surfaces through noncovalent reversible bonds. In this work, a fluorinated oligo(ethylenesuccinamide), soluble in solvent benign for operators and environment, has been synthesized. It contains two opposite functional groups (perfluoropolyether segments and amidic groups) (SC2-PFPE) that provide water repellency while hydrophilicity is retained. Its performance has been tested on porous calcarenite and investigated by magnetic resonance imaging, water capillary absorption, and vapor diffusivity tests. The results demonstrate that SC2-PFPE modifies the wettability of porous substrates in a drastic and durable way and reduces the vapor condensation inside the pore space due to the perfluoropolyether segments that act at the air/surface interface.

The ruthenium(II) complexes RuH 2 (CO) 2 (P n Bu 3 ) 2 , RuH 2 (CO) 2 (PPh 3 ) 2 , and RuH 2 (PPh 3 ) 4 are catalytically active in the hydrogenation of organic substrates containing a N@N, N(O)@N or NO 2 group. The reduction of the first two groups leads to hydrazine as intermediate and amine as the final product, while reducing a NO 2 group the corresponding amine is selectively formed. A complete conversion was reached, depending on temperature, catalyst and substrate concentration. The catalysts are also active in the hydrogenolysis of an N-N group giving the corresponding amine with a 97.3% conversion using RuH 2 (PPh 3 ) 4 as catalyst. A firstorder reaction rate with respect to substrate, catalyst or hydrogen pressure was detected in all cases. Finally, the activation parameters and the kinetic constants of these reactions were calculated. In the hydrogenation of azobenzene, the rate determining step involves an associative or a dissociative step depending on the catalyst employed while in the hydrogenation of all other substrates an associative rate determining step is always involved. A catalytic cycle is suggested for the hydrogenation of azobenzene, taking into account the intermediate complexes identified in the reaction medium.

Some oligo-or polyamides containing several hydroxyl groups were synthesized in order to obtain new water-soluble compounds with a high affinity for polar materials as wood, paper, and natural fibers. The interest for the synthetic procedures is the use of renewable sources as starting compounds. In fact natural compounds or their derivatives, as L-tartaric acid, D(þ)-glucaric acid and a,a-trehaluronic acid, were used as dicarboxylic acids in the polycondensation reactions, in order to obtain several functionalized oligoamides. All the compounds obtained in this study were characterized through FTIR and NMR spectroscopy. The oligoamides, water-soluble and not provided with high-molecular weights, were tested as wood consolidants. Physical properties like hygroscopicity of stabilized wood, volume shrinkage, density, and basic density were evaluated on the treated samples and compared with those obtained in the same conditions for an untreated archeological sample and a recent wood sample.

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The reactivity of phosphine substituted ruthenium carbonyl carboxylates Ru(CO) 2 (MeCOO) 2 (PBu 3 ) 2 , Ru 2 (CO) 4 (lMeCOO) 2 (PBu 3 ) 2 , Ru 4 (CO) 8 (l-MeCOO) 4 (PBu 3 ) 2 with H 2 and/or acetic acid was investigated by IR and NMR spectroscopy to clarify their role in the catalytic hydrogenation of acetic acid. Evidences were collected to suggest hydride ruthenium complexes as the catalytically active species. Equilibria among ruthenium hydrides and carboxylato complexes take place in the presence of hydrogen and acetic acid, that is in the conditions of the catalytic reaction. Nevertheless the presence of acetic acid reduces the rate of the formation of hydrides. Working at a very high temperature (180°C) polynuclear phosphido hydrides such as [Ru 6 (l-H) 6 (CO) 10 (l-PHBu)(l-PBu 2 ) 2 (PBu 3 ) 2 (l 6 -P)] were formed. These phosphido clusters are suggested as the resting state of the catalytic system.Furthermore the bi-or tetranuclear Ru(I) carboxylato complexes react with acetic acid giving a mononuclear ruthenium complex Ru(CO) 2 (MeCOO)(l-MeCOO)(PBu 3 ), containing a monodentate and a chelato acetato ligands. This complex was spectroscopically characterised. Its identity and structure were confirmed by its reactivity with stoichiometric amount of PPh 3 to give Ru(CO) 2 (Me-COO) 2 (PBu 3 )(PPh 3 ), a new mononuclear ruthenium carbonyl carboxylate containing two different phosphines, that was fully characterised.