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Modulation of a Supramolecular Figure-of-Eight Strip Based on a Photoswitchable Stiff-Stilbene.

ABSTRACT: The preparation, assembly and dynamic properties of photoswitchable bisphosphine ligands based on the stiff-stilbene scaffold are reported. Directional bonding and coordination-induced assembly allow complexation of these ligands with palladium(II), resulting in the formation of discrete metallo-supramolecular entities. While the Z isomer forms a simple bidentate metallo-macrocycle, an intricate double helicate figure-of-eight dimer is observed with the E ligand. Topologically 3D complexes can thus be obtained from 2D ligands. Upon irradiation with UV light, isomerization of the ligands allows control of the architecture of the formed complexes, resulting in a light-triggered modulation of the supramolecular topology. Furthermore, a mechanistic investigation unveiled the dynamic nature of the helicate chirality, where a transmission of motion from the palladium centers yields an "eight-to-eight" inversion.

SUBMITTER: Costil R

PROVIDER: S-EPMC7384132 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Modulation of a Supramolecular Figure-of-Eight Strip Based on a Photoswitchable Stiff-Stilbene.

Costil Romain R Crespi Stefano S Pfeifer Lukas L Feringa Ben L BL

Chemistry (Weinheim an der Bergstrasse, Germany) 20200603 35

The preparation, assembly and dynamic properties of photoswitchable bisphosphine ligands based on the stiff-stilbene scaffold are reported. Directional bonding and coordination-induced assembly allow complexation of these ligands with palladium(II), resulting in the formation of discrete metallo-supramolecular entities. While the Z isomer forms a simple bidentate metallo-macrocycle, an intricate double helicate figure-of-eight dimer is observed with the E ligand. Topologically 3D complexes can t ...[more]

PMID: 32343010

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