Thermal polymorphic transformation of p-tert-Butylcalix
Studies were made on the polymorphism of p-tert-butylcalix[4]arene derivatives having amino acid groups on the lower rim to stabilize their hydrophilic pseudocavity by circular intramolecular hydrogen bonding. The calixarenes exhibit a polymorphic transformation upon heating in the solid state. This transformation is controlled by the thermal history of solids, accompanying the change on the conformation of the calixarene skeleton and also the change of hydrogen bonding in the hydrophilic pseudocavity.
Nomura
E
Industrial Technology Center of Wakayama Prefecture, 60 Ogura, Wakayama 649-6261, Japan.
Takagaki
M
Nakaoka
C
Taniguchi
H