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The first aim of the present study is the development of a new ruthenium(III) complex, belonging to NAMI-A class, with a potentially high cytotoxic ability. The presence of a fully protected sugar moiety as ruthenium ligand should increase the complex ability to cross cellular membranes. Furthermore, it sets this molecule in the area of biocompatible agents as tumor drug. The second, more relevant, purpose is to verify the ruthenium complexes activity after loading into liposomes. We reported the characterization and in vitro biological assays of pyridine derivatives of ruthenium complexes loaded into Egg l -α-phosphatidylcholine cholesterol/DSPE-PEG liposomes. Dynamic light scattering estimates that the sizes of all obtained liposomes are in the 100 nm range. This value is suitable for in vivo use. The loading ability and release kinetic allowed selecting the best ratio between the lipid fraction and metal to be tested in cellular experiments. The growth inhibitory effects of both liposomal and free complex in PC-3 prostate cancer cell lines demonstrate a high cytotoxic ability of the liposome entrapped ruthenium (III) complex suggesting additional role further the antimetastatic function.

This communication describes extremely efficient homogeneous iron(III) catalysts for the synthesis of solketal from glycerol and acetone. The activities are the highest ever reported so far for this type of reaction, with TOFs up to 10 5 h − 1 at negligible catalyst loading.

New Zn-based catalysts are described that act as heterogenized or heterogeneous catalysts, with easy recovery and re-utilization with a limited or even zero Zn-leaching. For stabilizing in the heterogeneous form the catalytically active Zn centre, mixed oxides, ZIF-8 and Zn-tethered systems have been synthesized and found to sensibly reduce the leaching of Zn in solution with respect to ZnO, making possible their recovery and reuse. ZIF-8 can be used for long time of reaction, reaching high DEC yields (comparable or higher than those obtained with ZnO) without any significant loss of zinc.

It is described the simple design of a series of N,N′,O,O′-chiral ligands (elpaN-salen-H2), which represent a subset of the elpaN-type library of ligands based on β-1,2- d -glucodiamine. The corresponding Mn(III) complexes were examined in the asymmetric epoxidation of styrenes with satisfactory results, e.g. cis-β-methylstyrene was functionalised in ees up to 88%.

New zinc(II) compounds containing functionalized Schiff bases have been prepared and characterized. The complexes catalyze the transesterification of soybean oil in mild conditions, and their activity can be modulated by a fine selection of the anions and/or of the substituents on the ancillary bidentate ligand. The compounds are active in the esterification of fatty acids and could therefore also be used to produce biodiesel from waste oils.

The simple synthesis of new O,N,O′-tridentate ligands derived from carbohydrates is illustrated. The ligands are obtained by condensing 2-amino-α- d -glucosides or 2-amino-α- d -alloside with several 3,5-disubstituted-2-hydroxybenzaldehydes. The efficiency of the imines in the V(IV)-promoted asymmetric oxidation of thioanisole has been examined and ee's up to 60% have been achieved.

New chiral P,N-chelates o-Ph2PC6H4CHNR (R=carbohydrate residue) derived from d -glucose and d -mannose were described. The synthesis of palladium(0) and rhodium(I) complexes of respective formula [Pd(P,N-chelate)(fumarodinitrile)] and [Rh(1,5-cyclooctadiene)(P,N-chelate)]BF4 was performed. It was found that the ligands effectively discriminate between the enantioface of fumarodinitrile in the Pd(0) species, prompting up to 100% diastereomeric excess when R is a 2,3,4-tri-O-acetylated glucoside moiety linked to N through C6. The catalytic activity of the complexes towards allylic alkylation and olefin hydroboration was also examined.

Complexes of a tertiary diphosphine with cyclic core, cis - P , P ′-diphenyl-1,4-diphospha-cyclohexane (dpdpc), with metal ions of Groups 9 and 10 have been prepared and characterised. In neutral M(0) or M(II) (M=Pt, Pd) complexes the diphosphine acts as a bridge affording polynuclear products. Instead, in cationic mononuclear Pt(II) and Pd(II) species a clear preference for chelation of dpdpc is observed. Also the cation [Ni(dpdpc) 2 Cl] + contains the two dpdpc moieties as chelates. The molecular and crystal structure of [Ni(dpdpc) 2 Cl] 2 (NiCl 4 ) discloses a significantly small bite angle of the chelate and interaction of near phenyl rings pertaining to opposite dpdpc moieties. Coordination of dpdpc to cobalt prompts its oxidation to the corresponding P , P ′-dioxide.

New chiral diimino and diamino ligands derived from α- d -mannose and α- d -glucose are described. The ligands are obtained by introducing the appropriate nitrogen functions at C(2) and C(3) of the sugar rings. The ability of the new chelates to promote the asymmetric copper(I)-catalysed cyclopropanation of styrene has been investigated. The nature of both the sugars and the chelates is crucial in determining the enantioselectivity of the reaction.