Kinetic control of threading of cyclodextrins onto axle molecules.
We report here, for the first time, kinetic control of the face-direction of cyclodextrin (CD) in the construction of a pseudo-rotaxane with an alkyl chain bearing pyridyl end caps. The yields of complexes of CDs with guest alkyl derivatives were controlled by the simple change of the position and the number of methyl groups bound to the pyridyl moiety. Single-substituted pyridyl groups attached to the ends of the alkyl chain regulated the rate for CDs passing them. Two methyl substituents could clearly govern the degree of complex formation of CD with guest molecules and resulted in the distinction of face-direction of CD molecules entering the gates at guest ends.
Oshikiri
Tomoya
T
Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
Takashima
Yoshinori
Y
Yamaguchi
Hiroyasu
H
Harada
Akira
A