Synthesis of butadiyne-bridged [4n] metacyclophanes having exo-annular t-butyl groups
Butadiyne-bridged [44]- and [48]metacyclophanes having exo-annular t-butyl groups were prepared by intermolecular Eglinton coupling of the dimeric unit or by intramolecular ring closure of the linear tetramer. Comparison of the 1H and 13C NMR spectra of [44]metacyclophane with those of [48]cyclophane and diphenylbutadiyne revealed its prominent geometrical feature due to deformation of the triple bonds from linearity. The [44]Metacyclophane was converted into [08]thiophenometacyclophane in good yield by treatment with sodium sulfide.
Synthesis and self-association properties of diethynylbenzene macrocycles
We synthesized diethynylbenzene macrocycles (DBMs), cyclic oligomers of diethynylbenzene, having functional groups in the periphery of the macrocyclic framework and investigated their self-association properties in solution resulting from π-π stacking interaction. The tetrakis-DBM having hexadecyl ester groups showed dimerization behavior not only in chloroform-d, but also in o-dichlorobenzene-4.