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Light triggers molecular shuttling in rotaxanes: control over proximity and charge recombination.

ABSTRACT: We present the synthesis of novel rotaxanes based on mechanically interlocked porphyrins and fullerene and their advanced investigations by means of photophysical measurements. To this end, a fullerene-capped dumbbell-type axle containing a central triazole was threaded through strapped (metallo)porphyrins-either a free-base or a zinc porphyrin. Femtosecond-resolved transient absorption measurements revealed charge-separation between the porphyrin and fullerene upon light excitation. Solvent polarity and solvent coordination effects induced molecular motion of the rotaxanes upon charge separation and enabled, for the first time, subtle control over the charge recombination by enabling and controlling the directionality of shuttling.

SUBMITTER: Wolf M

PROVIDER: S-EPMC6446966 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Light triggers molecular shuttling in rotaxanes: control over proximity and charge recombination.

Wolf Maximilian M Ogawa Ayumu A Bechtold Mareike M Vonesch Maxime M Wytko Jennifer A JA Oohora Koji K Campidelli Stéphane S Hayashi Takashi T Guldi Dirk M DM Weiss Jean J

Chemical science 20190227 13

We present the synthesis of novel rotaxanes based on mechanically interlocked porphyrins and fullerene and their advanced investigations by means of photophysical measurements. To this end, a fullerene-capped dumbbell-type axle containing a central triazole was threaded through strapped (metallo)porphyrins-either a free-base or a zinc porphyrin. Femtosecond-resolved transient absorption measurements revealed charge-separation between the porphyrin and fullerene upon light excitation. Solvent pol ...[more]

PMID: 30996970

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