4,6-Dimethyl-α-pyrone (Me21) has been used in the preparation of G4C{Me21} via reacting with tetra-p-sulfocalix[4]arene (C) and guanidine hydrochloride (GCl). It may be used in the preparation of host-guest complex G4C{Me21} by reacting with crystalline guanidinium-sulfonate-calixarene (G4C). This complex on UV irradiation afforded 1,3-dimethylcyclobutadiene (Me2CBD).
4,6-Dimethyl-α-pyrone was immobilized in a guanidinium-sulfonate-calixarene (G4C) crystalline network, which upon exposure to ultraviolet irradiation, transforms the entrapped 4,6-dimethyl-α-pyrone into a 4,6-dimethyl-β-lactone. Thin solid films layers of 4,6-dimethyl-α-pyrone on UV irradiation at -190°C were investigated.