CH/π Interactions as Demonstrated in the Crystal Structure of Host/Guest Compounds. A Database Study

Crystal structures deposited in the Cambridge Structural Database (CSD) were examined, by use of our program CHPI, for several kinds of clathrates in order to know the role of the CH/π interaction in host/guest chemistry. These include cyclodextrin complexes, calix[4]arene complexes, cryptophane complexes and pseudorotaxanes. A number of short CH/π distances have been shown in the crystal structure of these compounds. The result was discussed in view of the role of the CH/π interaction in controlling the specific structure of supramolecules.