title: Molecular acrobatics: self-assembly of calixarene-porphyrin cages.
abstract: Calix[4]arenes equipped with two and four zinc porphyrins have been prepared, and they show remarkable flexibility in their self-assembly properties with the bidentate ligand DABCO. The calix-bisporphyrin forms a 2:2 complex with DABCO, generating a large cavity that has the potential to act as a supramolecular host. The calix-tetraporphyrin, on the other hand, forms four different complexes with DABCO depending on the stoichiometry and concentration. During the course of a titration, all four complexes are populated, leading to large conformational changes and the formation of both intramolecular and intermolecular calix-tetraporphyrin-DABCO sandwich complexes. The system was fully characterized using a combination of UV-visible and (1)H NMR spectroscopy to identify the complexes. At a calix-tetraporphyrin:DABCO ratio of 2:4, the major species is dimeric cage assembly that features a large internal cavity for guest complexation.
authors: Dipartimento di Chimica Organica e Industriale, Universitá di Parma, Italy.
authors: Laura
authors: L
authors: Baldini
authors: Pablo
authors: P
authors: Ballester
authors: Alessandro
authors: A
authors: Casnati
authors: Rosa M
authors: RM
authors: Gomila
authors: Christopher A
authors: CA
authors: Hunter
authors: Francesco
authors: F
authors: Sansone
authors: Rocco
authors: R
authors: Ungaro