ol7b01231_si_002.cif (6.61 MB)
Download file

Synthesis of [8]Cycloparaphenylene-octacarboxylates via Rh-Catalyzed Stepwise Cross-Alkyne Cyclotrimerization

Download (6.61 MB)
posted on 17.05.2017, 00:00 authored by Norihiko Hayase, Yuta Miyauchi, Yukimasa Aida, Haruki Sugiyama, Hidehiro Uekusa, Yu Shibata, Ken Tanaka
The synthesis of C4- and C2-symmetrical [8]­cycloparaphenylene (CPP)-octacarboxylates has been achieved via macrocyclization by the rhodium-catalyzed intermolecular stepwise cross-cyclotrimerization and subsequent reductive aromatization. The C4-symmetrical octa-tert-butyl [8]­CPP-octacarboxylate forms a dimer in which eight ester moieties face each other. The dimers are aligned so as to make a one-dimensional column with a channel structure inside. Both absorption and fluorescence maxima of [8]­CPP-octacarboxylates in CHCl3 were significantly blue-shifted compared to those of [8]­CPP due to the presence of eight electron-withdrawing ester moieties.