Dynamic donor-acceptor [2]catenanes

Abstract

Donor-acceptor [2]catenanes based on cyclobis(paraquat-p-phenylene) as the π-acceptor ring have been used prominently in the construction of functional molecular devices. We report here their thermodynamically controlled synthesis from isolated π-donor and π-acceptor rings under the catalytic influence of tetrabutylammonium iodide. The initial nucleophilic attack of iodide ion, which opens up the π-acceptor ring, is followed by complexation to the π-donor ring and the subsequent catenation of the π-donor ring by the π-acceptor ring [2]catenane. The reaction is general in scope and proceeds in high yields, without giving rise to side-products. © 2007 by The National Academy of Sciences of the USA.