The exclusive self-sorting observed in the self-assembly process between tetraurea benzyl calix[4]pyrroles and tetraurea tolyl calix[4]arene to afford unprecedented hybrid dimeric capsules with polar interiors is described. The coencapsulation of a solvent molecule with an organic guest yields four particle aggregates in which the guests are confined and restricted into single hemispheres due to the polar requirements of the internal cavity.
![Exclusive self-assembly of a polar dimeric capsule between tetraurea calix[4]pyrrole and tetraurea calix[4]arene](https://www.iciq.org/wp-content/uploads/2014/03/Exclusive-self-assembly_3402.gif)