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

Org Lett. 2017 Jun 2;19(11):2993-2996. doi: 10.1021/acs.orglett.7b01231. Epub 2017 May 17.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't