RT Journal Article
T1 Conjugated Porphyrin Dimers: Cooperative Effects and Electronic Communication in Supramolecular Ensembles with C60
A1 Moreira, Luis
A1 Calbo, Joaquín
A1 Aragó, Juan
A1 Illescas, Beatriz M.
A1 Nierengarten, Iwona
A1 Delavaux-Nicot, Béatrice
A1 Ortí, Enrique
A1 Martín, Nazario
A1 Nierengarten, Jean-Françoise
AB Two new conjugated porphyrin-based systems (dimers 3 and 4) endowed with suitable crown ethers have been synthesized as receptors for a fullerene-ammonium salt derivative (1). Association constants in solution have been determined by UVvis titration experiments in CH2Cl2 at room temperature. The designed hosts are able to associate up to two fullerene-based guest molecules and present association constants as high as 5 × 108 M‒1. Calculation of the allosteric cooperative factor  for supramolecular complexes [3·12] and [4·12] showed a negative cooperative effect in both cases. The interactions accounting for the formation of the associates are based, firstly, on the complementary ammonium-crown ether interaction and, secondly, on the π−π interactions between the porphyrin rings and the C60 moieties. Theoretical calculations have evidenced a significant decrease of the electron density in the porphyrin dimers 3 and 4 upon complexation of the first C60 molecule, in good agreement with the negativecooperativity found in these systems. This negative effect is partially compensated by the stabilizing C60-C60 interactions that take place in the more stable syn-disposition of [4·12].
PB ACS
SN 1520-5126 (Online)  0002-7863 (Print)
YR 2016
FD 2016-09
LK https://hdl.handle.net/20.500.14352/17675
UL https://hdl.handle.net/20.500.14352/17675
LA eng
NO Unión Europea. FP7
NO Ministerio de Economía y Competitividad (MINECO)
NO Comunidad de Madrid
NO Generalitat Valenciana
DS Docta Complutense
RD 30 abr 2024