Calixphyrins: Novel Macrocycles at the Intersection between Porphyrins and Calixpyrroles

Blending porphyrins and calixpyrroles, the calix[n]phyrins 1 (n=4, 6, 8; x=1, 2, 3; Ar=C6H2(CH3)3) are easily prepared by condensing an appropriately functionalized dipyrromethane with acetone followed by oxidation with 4,5-dichloro-3,6-dioxo-1,2-benzenedinitrile. The structure of these molecules show a competition between planar porphyrinic and cuplike calixarene elements. These molecules bind both anions and cations.