A novel class of self-folding velcrands was prepared that dimerize through
intermolecular forces. Solvophobic interactions on extended pi surfaces sta
bilize the dimer similar to velcrands, while eight hydrogen bonds act like
snaps to hold the molecules together. The self-complementary array of hydro
gen bonding sites were incorporated on the upper rim of a resorcinarene-bas
ed cavitand. A dramatic reorganization of shape and size of the internal ca
vity was manifested through changes in solvent polarity. Specifically, the
equilibrium between the extended surface (D-2d symmetry) and a deep cavity
(C-4v symmetry) could be manipulated in mixtures of aromatic solvents (or C
DCl3) and [D-6]DMSO. The switching of conformations and the dimerization mo
tif are well-suited for the assembly of noncovalent polymeric materials.