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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - 2,7- and 4,9-Dialkynyldihydropyrene Molecular Switches: Syntheses, Properties, and Charge Transport in Single-Molecule Junctions
AU - Roemer, Max
AU - Gillespie, Angus
AU - Jago, David
AU - Costa-Milan, David
AU - Alqahtani, Jehan
AU - Hurtado-Gallego, Juan
AU - Sadeghi, Hatef
AU - Lambert, Colin J.
AU - Spackman, Peter R.
AU - Sobolev, Alexandre N.
AU - Skelton, Brian W.
AU - Grosjean, Arnaud
AU - Walkey, Mark
AU - Kampmann, Sven
AU - Vezzoli, Andrea
AU - Simpson, Peter V.
AU - Massi, Massimiliano
AU - Planje, Inco
AU - Rubio-Bollinger, Gabino
AU - Agraït, Nicolás
AU - Higgins, Simon J.
AU - Sangtarash, Sara
AU - Piggott, Matthew J.
AU - Nichols, Richard J.
AU - Koutsantonis, George A.
PY - 2022/7/20
Y1 - 2022/7/20
N2 - This paper describes the syntheses of several functionalized dihydropyrene (DHP) molecular switches with different substitution patterns. Regioselective nucleophilic alkylation of a 5-substituted dimethyl isophthalate allowed the development of a workable synthetic protocol for the preparation of 2,7-alkyne-functionalized DHPs. Synthesis of DHPs with surface-anchoring groups in the 2,7- and 4,9-positions is described. The molecular structures of several intermediates and DHPs were elucidated by X-ray single-crystal diffraction. Molecular properties and switching capabilities of both types of DHPs were assessed by light irradiation experiments, spectroelectrochemistry, and cyclic voltammetry. Spectroelectrochemistry, in combination with density functional theory (DFT) calculations, shows reversible electrochemical switching from the DHP forms to the cyclophanediene (CPD) forms. Charge-transport behavior was assessed in single-molecule scanning tunneling microscope (STM) break junctions, combined with density functional theory-based quantum transport calculations. All DHPs with surface-contacting groups form stable molecular junctions. Experiments show that the molecular conductance depends on the substitution pattern of the DHP motif. The conductance was found to decrease with increasing applied bias.
AB - This paper describes the syntheses of several functionalized dihydropyrene (DHP) molecular switches with different substitution patterns. Regioselective nucleophilic alkylation of a 5-substituted dimethyl isophthalate allowed the development of a workable synthetic protocol for the preparation of 2,7-alkyne-functionalized DHPs. Synthesis of DHPs with surface-anchoring groups in the 2,7- and 4,9-positions is described. The molecular structures of several intermediates and DHPs were elucidated by X-ray single-crystal diffraction. Molecular properties and switching capabilities of both types of DHPs were assessed by light irradiation experiments, spectroelectrochemistry, and cyclic voltammetry. Spectroelectrochemistry, in combination with density functional theory (DFT) calculations, shows reversible electrochemical switching from the DHP forms to the cyclophanediene (CPD) forms. Charge-transport behavior was assessed in single-molecule scanning tunneling microscope (STM) break junctions, combined with density functional theory-based quantum transport calculations. All DHPs with surface-contacting groups form stable molecular junctions. Experiments show that the molecular conductance depends on the substitution pattern of the DHP motif. The conductance was found to decrease with increasing applied bias.
KW - Colloid and Surface Chemistry
KW - Biochemistry
KW - General Chemistry
KW - Catalysis
U2 - 10.1021/jacs.2c02289
DO - 10.1021/jacs.2c02289
M3 - Journal article
VL - 144
SP - 12698
EP - 12714
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 28
ER -