Since the preparation of the first quinoxaline-bridged resorcin [4] arene cavitand by Cram and co-workers in 1982,[1] numerous derivatives with various structures and functions have been prepared and employed as switches,[2] receptors and sensors,[3] catalysts,[4] and molecular hosts.[5] The most fascinating feature of top-open resorcin [4] arene cavitands is their ability to adopt two spatially well-defined conformations: an expanded “kite” form and ...
