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Unveiling the nature of supramolecular crown ether-C60 interactions.

ABSTRACT: A series of exTTF-(crown ether)2 receptors, designed to host C60, has been prepared. The size of the crown ether and the nature of the heteroatoms have been systematically changed to fine tune the association constants. Electrochemical measurements and transient absorption spectroscopy assisted in corroborating charge transfer in the ground state and in the excited state, leading to the formation of radical ion pairs featuring lifetimes in the range from 12 to 21 ps. To rationalize the nature of the exTTF-(crown ether)2·C60 stabilizing interactions, theoretical calculations have been carried out, suggesting a synergetic interplay of donor-acceptor, ?-?, n-? and CH···? interactions, which is the basis for the affinity of our novel receptors towards C60.

SUBMITTER: Moreira L

PROVIDER: S-EPMC5665100 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Unveiling the nature of supramolecular crown ether-C60 interactions.

Moreira Luis L Calbo Joaquín J Krick Calderon Rafael M RM Santos José J Illescas Beatriz M BM Aragó Juan J Nierengarten Jean-François JF Guldi Dirk M DM Ortí Enrique E Martín Nazario N

Chemical science 20150518 8

A series of exTTF-(crown ether)2 receptors, designed to host C60, has been prepared. The size of the crown ether and the nature of the heteroatoms have been systematically changed to fine tune the association constants. Electrochemical measurements and transient absorption spectroscopy assisted in corroborating charge transfer in the ground state and in the excited state, leading to the formation of radical ion pairs featuring lifetimes in the range from 12 to 21 ps. To rat ...[more]

PMID: 29142697

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