Preparation of a Cyclic Polyphenylene Array for a Chiral-Type Carbon Nanotube Segment

Abstract

DielsAlder reaction of cyclic biphenylyleneacetylene compound 3 with tetraphenylcyclopentadienone (5) realized the preparation of large-sized cyclic polyphenylene array 4. This is the first example of a cyclic polyphenylene array with a complete ring arrangement of a chiral-type CNT segment with (12,3)-structure. Transformation of 4 to the chiral-type CNT segment was attempted, but resulted in the formation of a complicated mixture probably due to the partial dehydrogenation and/or the partial elimination about the long alkyl chains. Rather efficient blue emission of the cyclic compounds 3 and 4 was discussed utilizing fluorescence quantum efficiencies and lifetimes both in their solid state and in their solution. By thermal analyses triple-melting behavior of 3 was clarified.

Chiral Buckybowl Molecules

“…In this short review, we summarize recent progress on the stereochemistry of buckybowls and their derivatives. It covers recent developments in the asymmetric synthesis and optical resolution of buckybowls from their racemates, and application of the enantioenriched buckybowls in the chiral aggregate formation and homochiral CNT syntheses [45,46]. These structurally well-defined single-chiral CNTs exploit truly exciting applications ranging from space elevator to armchair quantum wire and bio-related applications [47].…”