TY - JOUR
T1 - Counterintuitive affinity of [2.2]paracyclophane to cations
AU - Quiñonero, David
AU - Frontera, Antonio
AU - Garau, Carolina
AU - Ballester, Pau
AU - Costa, Antoni
AU - Deyà, Pere M.
AU - Pichierri, Fabio
N1 - Funding Information:
We thank the DGICYT (Projects BQU-2002-04651) for financial support. We thank the CESCA for computational facilities. C.G. thanks the MEC for a pre-doctoral fellowship. A.F. and D.Q. thank the MCyT for a ‘Ramón y Cajal’ and a ‘Juan de la Cierva’ contract, respectively. F.P. thanks the 21st century COE project ‘Giant Molecules and Complex Systems’ for financial support.
PY - 2005/6/7
Y1 - 2005/6/7
N2 - Geometries and binding energies of complexes of cations with benzene, [2.2]paracyclophane and a [2.2]paraheterocyclophane are computed and compared using ab initio calculations. [2.2]Paracyclophane is not used for building cation receptors because of its small cavity. Here, we demonstrate that its binding capability toward cations using one aromatic ring is superior to benzene in ∼10 kcal/mol. This unexpected difference is explained by the reduction, upon complexation, of the repulsive interaction of the π-systems, which is due to the close proximity of the two benzene rings. Experimental results derived from the analysis of X-ray structures retrieved from the CSD support this explanation.
AB - Geometries and binding energies of complexes of cations with benzene, [2.2]paracyclophane and a [2.2]paraheterocyclophane are computed and compared using ab initio calculations. [2.2]Paracyclophane is not used for building cation receptors because of its small cavity. Here, we demonstrate that its binding capability toward cations using one aromatic ring is superior to benzene in ∼10 kcal/mol. This unexpected difference is explained by the reduction, upon complexation, of the repulsive interaction of the π-systems, which is due to the close proximity of the two benzene rings. Experimental results derived from the analysis of X-ray structures retrieved from the CSD support this explanation.
UR - http://www.scopus.com/inward/record.url?scp=18844435743&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=18844435743&partnerID=8YFLogxK
U2 - 10.1016/j.cplett.2005.03.150
DO - 10.1016/j.cplett.2005.03.150
M3 - Article
AN - SCOPUS:18844435743
SN - 0009-2614
VL - 408
SP - 59
EP - 64
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 1-3
ER -