Hybrid calix[4]arenes via ionic hydrogenation and transition-metal-mediated processes.

We report the first application of ionic hydrogenation for the synthesis of upper-rim urea- or carbamate-derived hybrid calix[4]arenes. Subsequent metal-mediated transformations using 4-iodophenylurea calixarenes afforded structurally unique 1,3-di(biaryl)-, 1,3-di(biarylalkyne)-, or 1,3-(biaryl)(biarylalkyne)-derived hybrid calixarenes. © 2009 American Chemical Society.