Thermally induced reversible conformational changes in the host–guest adduct of meso-tetramethyltetrakis(ethyl)calix[4]pyrrole

The binding of methanol, ethanol, and N,N-dimethylformamide to meso-tetramethyltetrakis(ethyl)calix[4]pyrrole (1) was investigated in both solid and solution with the exhibition of multi-fashion hydrogen bonding as shown by X-ray crystallography. The thermodynamic stability of these host–guest inclusion complexes were determined by exploiting TGA and DTA. An unexpected conformational change in 1·2EtOH occurred by thermal induction.