Two kinds of glutamaic acid-based coumarin derivatives show a quite different trend against gelation in organic solvents in terms of inter- or intramolecular hydrogen bonds involved. It has been found out that addition of the valinate structure into the coumarine derivative could improve its gelation ability.Download high-res image (101KB)Download full-size image

Dithia[3.3]metacyclophanes which consist of the pyridine unit connecting to the different positions of the parent cyclophane skeleton have been prepared. Conformational change has been observed for the cyclophane having a 4-substituted pyridine unit by binding to the porphyrin. In contrast the porphyrin binding has no influence on conformational behavior of the cyclophane having a 3-substituted pyridine unit.

Dithia[3.3](4,9)benzenopyrenophanes carrying various functional groups at the inner position or the outer position of the benzene ring have been prepared. The pyrenophanes with the substituent at the inner position of the opposite benzene ring exhibit the conformation in which the pyrene and the benzene components exist in the parallel manner (parallel conformation). On the contrary the conformation characterized by the perpendicular orientation of the pyrene and the benzene components has been confirmed for the pyrenophanes having the substituent at the outer position of the opposite benzene ring (perpendicular conformation). The NH–π interaction between the inner amino group on the opposite benzene ring and the pyrene ring was observed. Formation of charge-transfer complexes of the pyrenophanes and tetracyanoethylene (TCNE) was performed. It has been found out that the orientation of two aromatic components and the NH–π interaction as well as the electronic nature of the substituent on the opposite benzene ring significantly affect characteristics of the charge-transfer complexes in this pyrenophane system.