Indication of Pd-C or Cu-C Intermediate in Respective Bimetallic Nanoclusters Pd/Au-PVP or Cu/Au-PVP Catalyzed Oxidations of -4-Oxatricyclo[5.2.1.0]-8-decene and Tetrahydro-γ-carbolines.

Catalytic oxidations of tricyclic -norbornene-fused tetrahydrofuran with bimetallic nanoclusters Cu/Au-PVP and HO or -BuOOH as an oxidant provided C-H bond oxidation adjacent to the ether function and 4-oxa-tricyclo[5.2.1.

Synthesis and Characterization of Bimetallic Nanoclusters Stabilized by Chiral and Achiral Polyvinylpyrrolidinones. Catalytic C(sp)-H Oxidation.

Second-generation chiral-substituted poly--vinylpyrrolidinones (CSPVPs) (-)- and (+)- were synthesized by free-radical polymerization of (3a,6a)- and (3a,6a)-5-ethenyl-tetrahydro-2,2-dimethyl-4-1,3-dioxolo[4,5-]pyrrol-4-one, respectively, using thermal and photochemical reactions. They were produced from respective -isoascorbic acid and d-ribose. In addition, chiral polymer (-)- was also synthesized from the polymerization of ()-3-(methoxymethoxy)-1-vinylpyrrolidin-2-one.

Cu recognition by N,N'-benzylated bis(amino amides).

Two new C-symmetric N,N'-benzylated bis(amino amides) have been synthesised and their interaction with different transition metals studied using a variety of techniques including UV-Vis and CD spectroscopy or ESI-MS. The determination of the corresponding stability constants with Cu has been possible, in HO/CHCN 7/3 v/v, for one of these ligands (4) using potentiometric titrations. The results obtained reveal that N-benzylation affords significant changes to their properties and is accompanied by an appreciable decrease in the corresponding complexation stability constants.

Cu(2+), Zn(2+), and Ni(2+) Complexes of C2-Symmetric Pseudopeptides with an Aromatic Central Spacer.

Two new tetradentate C2-symmetric pseudopeptidic ligands derived from Val and Phe containing two amino and two amido groups and a central o-substituted aromatic spacer have been prepared. Their complexes with Cu(2+), Zn(2+), and Ni(2+) have been studied by potentiometry, UV-vis spectrophotometry, FT-IR, and ESI-MS. The presence of the aromatic spacer provides Cu(2+) complexes with stability constants several orders of magnitude higher than those observed for related ligands containing aliphatic central spacers.