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The synthesis of three new amido-imine-type hybrid macrocycles based on substituted pyrrole units showed them to act as effective receptors for oxoanions in the solid state and in acetonitrile solution. The acetonitrile solution using standard UV-vis spectroscopic titration methods indicated that the three new receptors display high affinities toward oxoanions with maximal association constants being on the order of [10.sup.7] [M.sup.-1].

The synthesis, characterization, and anion-binding properties of a series of 2,6-diamidopyridine dipyrromethane hybrid macrocyles are discussed. Results show that by changing the flexibility, cavity size, the directionality of anion-binding moieties in the macrocyclic framework, the anion selectivity can change dramatically.

The anion templated condensation of dialdehyde and diamine building blocks was used to synthesize the large oligopyrrolic macrocyclic receptors. The X-ray crystal structure of complex revealed anion binding in a 1:1 fashion in the solid state through a complementary hydrogen bond network involving both the receptor and the anions.

An electrophilic trifluoromethylation of ketene silyl acetals (KSAs) by hypervalent iodine reagents 1 and 2 has been developed. The reaction proceeds under very mild conditions in the presence of a catalytic amount of trimethylsilyl bis(trifluoromethanesulfonyl)imide (up to 2.5 mol %) as a Lewis acid providing a direct access to a variety of secondary, tertiary, and quaternary a-trifluoromethyl esters and lactones in high yield (up to 98%). [ABSTRACT FROM AUTHOR]

Diiminodipyrromethane complexes of Ni, Pd, and Pt are able to activate O2, resulting in a metal-dependent autoxidation of the ligand. [ABSTRACT FROM AUTHOR]